64-bit has removed the sync from _switch since commit 9145effd62
("powerpc/64: Drop explicit hwsync in context switch"). The same
logic there should apply to 32-bit. Remove the sync and replace with
a placeholder comment (32 and 64 will be merged with a later change).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-4-npiggin@gmail.com
More some 64-bit specifics out from the function epilogue and rearrange
this to be a bit neater, use 32-bit mem ops for CR save/restore, and
change some register numbers.
This is preparation to consolidate 32-bit and 64-bit switch code.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-3-npiggin@gmail.com
The large hunk of SLB pinning in _switch asm code makes it more
difficult to see everything else that's going on. It is a less important
path now, so icache and fetch footprint overhead can be avoided.
Move context switch stack SLB pinning out of line.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230606132447.315714-2-npiggin@gmail.com
With SERIAL_8250=y and SERIAL_8250_FSL_CONSOLE=n the both
IS_ENABLED(CONFIG_SERIAL_8250) and IS_REACHABLE(CONFIG_SERIAL_8250)
evaluate to true and so fsl8250_handle_irq() is used. However this
function is only available if CONFIG_SERIAL_8250_CONSOLE=y (and thus
SERIAL_8250_FSL=y).
To prepare SERIAL_8250_FSL becoming tristate and being enabled in more
cases, check for IS_REACHABLE(CONFIG_SERIAL_8250_FSL) before making use
of fsl8250_handle_irq(). This check is correct with and without the
change to make SERIAL_8250_FSL modular.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: 66eff0ef52 ("powerpc/legacy_serial: Warn about 8250 devices operated without active FSL workarounds")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Message-ID: <20230609133932.786117-2-u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Do a search and replace of:
- NMI_WATCHDOG_ENABLED => WATCHDOG_HARDLOCKUP_ENABLED
- SOFT_WATCHDOG_ENABLED => WATCHDOG_SOFTOCKUP_ENABLED
- watchdog_nmi_ => watchdog_hardlockup_
- nmi_watchdog_available => watchdog_hardlockup_available
- nmi_watchdog_user_enabled => watchdog_hardlockup_user_enabled
- soft_watchdog_user_enabled => watchdog_softlockup_user_enabled
- NMI_WATCHDOG_DEFAULT => WATCHDOG_HARDLOCKUP_DEFAULT
Then update a few comments near where names were changed.
This is specifically to make it less confusing when we want to introduce
the buddy hardlockup detector, which isn't using NMIs. As part of this,
we sanitized a few names for consistency.
[trix@redhat.com: make variables static]
Link: https://lkml.kernel.org/r/20230525162822.1.I0fb41d138d158c9230573eaa37dc56afa2fb14ee@changeid
Link: https://lkml.kernel.org/r/20230519101840.v5.12.I91f7277bab4bf8c0cb238732ed92e7ce7bbd71a6@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Colin Cross <ccross@android.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Lecopzer Chen <lecopzer.chen@mediatek.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masayoshi Mizuma <msys.mizuma@gmail.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Tzung-Bi Shih <tzungbi@chromium.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
cachestat is previously only wired in for x86 (and architectures using
the generic unistd.h table):
https://lore.kernel.org/lkml/20230503013608.2431726-1-nphamcs@gmail.com/
This patch wires cachestat in for all the other architectures.
[nphamcs@gmail.com: wire up cachestat for arm64]
Link: https://lkml.kernel.org/r/20230511092843.3896327-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20230510195806.2902878-1-nphamcs@gmail.com
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com> [s390]
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Looking at generated code for handle_signal32() shows calls to a
function called __unsafe_save_user_regs.constprop.0 while user access
is open.
And that __unsafe_save_user_regs.constprop.0 function has two nops at
the begining, allowing it to be traced, which is unexpected during
user access open window.
The solution could be to mark __unsafe_save_user_regs() no trace, but
to be on the safe side the most efficient is to flag it __always_inline
as already done for function __unsafe_restore_general_regs(). The
function is relatively small and only called twice, so the size
increase will remain in the noise.
Do the same with save_tm_user_regs_unsafe() as it may suffer the
same issue.
Fixes: ef75e73182 ("powerpc/signal32: Transform save_user_regs() and save_tm_user_regs() in 'unsafe' version")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/7e469c8f01860a69c1ada3ca6a5e2aa65f0f74b2.1685955220.git.christophe.leroy@csgroup.eu
A disassembly of interrupt_exit_kernel_prepare() shows a useless read
of MSR register. This is shown by r9 being re-used immediately without
doing anything with the value read.
c000e0e0: 60 00 00 00 nop
c000e0e4: 7d 3a c2 a6 mfmd_ap r9
c000e0e8: 7d 20 00 a6 mfmsr r9
c000e0ec: 7c 51 13 a6 mtspr 81,r2
c000e0f0: 81 3f 00 84 lwz r9,132(r31)
c000e0f4: 71 29 80 00 andi. r9,r9,32768
This is due to the use of local_irq_save(). The flags read by
local_irq_save() are never used, use local_irq_disable() instead.
Fixes: 13799748b9 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/df36c6205ab64326fb1b991993c82057e92ace2f.1685955214.git.christophe.leroy@csgroup.eu
If the 8250 driver is built as a module (or built-in without console
support) the Freescale specific workaround were silently not activated.
Add a warning in this case.
Currently CONFIG_SERIAL_8250_FSL=y implies that the function
fsl8250_handle_irq() is built-in and can be used. However with the
changes of the next commit CONFIG_SERIAL_8250_FSL might be enabled also
when the 8250 driver is a module and so more care is needed when
fsl8250_handle_irq() is to be used. The code added here is able to
handle the new situation already.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-ID: <20230605130857.85543-2-u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that we have raw_atomic*_<op>() definitions, there's no need to use
arch_atomic*_<op>() definitions outside of the low-level atomic
definitions.
Move treewide users of arch_atomic*_<op>() over to the equivalent
raw_atomic*_<op>().
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230605070124.3741859-19-mark.rutland@arm.com
A future change will move CLANG_FLAGS from KBUILD_{A,C}FLAGS to
KBUILD_CPPFLAGS so that '--target' is available while preprocessing.
When that occurs, the following error appears when building the compat
PowerPC vDSO:
clang: error: unsupported option '-mbig-endian' for target 'x86_64-pc-linux-gnu'
make[3]: *** [.../arch/powerpc/kernel/vdso/Makefile:76: arch/powerpc/kernel/vdso/vdso32.so.dbg] Error 1
Explicitly add CLANG_FLAGS to ldflags-y, so that '--target' will always
be present.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
For an SR-IOV device, while enabling DDW, a new table is created and
added at index 1 in the group. In the below 2 scenarios, the table is
incorrectly referenced at index 0 (which is where the table is for
default DMA window).
1. When adding DDW
This issue is exposed with "slub_debug". Error thrown out from
dma_iommu_dma_supported()
Warning: IOMMU offset too big for device mask
mask: 0xffffffff, table offset: 0x800000000000000
2. During Dynamic removal of the PCI device.
Error is from iommu_tce_table_put() since a NULL table pointer is
passed in.
Fixes: 381ceda88c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping")
Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Gaurav Batra <gbatra@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230505184701.91613-1-gbatra@linux.vnet.ibm.com
When DMA window is backed by 2MB TCEs, the DMA address for the mapped
page should be the offset of the page relative to the 2MB TCE. The code
was incorrectly setting the DMA address to the beginning of the TCE
range.
Mellanox driver is reporting timeout trying to ENABLE_HCA for an SR-IOV
ethernet port, when DMA window is backed by 2MB TCEs.
Fixes: 3872731187 ("powerps/pseries/dma: Add support for 2M IOMMU page size")
Cc: stable@vger.kernel.org # v5.16+
Signed-off-by: Gaurav Batra <gbatra@linux.vnet.ibm.com>
Reviewed-by: Greg Joyce <gjoyce@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230504175913.83844-1-gbatra@linux.vnet.ibm.com
Now that power calls iommu_device_register() and populates its groups
using iommu_ops->device_group it should not be calling
iommu_group_remove_device().
The core code owns the groups and all the other related iommu data, it
will clean it up automatically.
Remove the bus notifiers and explicit calls to
iommu_group_remove_device().
Fixes: a940904443 ("powerpc/iommu: Add iommu_ops to report capabilities and allow blocking domains")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/0-v1-1421774b874b+167-ppc_device_group_jgg@nvidia.com
Back during the discussion of
commit a9a3ed1eff ("x86: Fix early boot crash on gcc-10, third try")
we discussed the need for a function attribute to control the omission
of stack protectors on a per-function basis; at the time Clang had
support for no_stack_protector but GCC did not. This was fixed in
gcc-11. Now that the function attribute is available, let's start using
it.
Callers of boot_init_stack_canary need to use this function attribute
unless they're compiled with -fno-stack-protector, otherwise the canary
stored in the stack slot of the caller will differ upon the call to
boot_init_stack_canary. This will lead to a call to __stack_chk_fail()
then panic.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94722
Link: https://lore.kernel.org/all/20200316130414.GC12561@hirez.programming.kicks-ass.net/
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20230412-no_stackp-v2-1-116f9fe4bbe7@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: ndesaulniers@google.com <ndesaulniers@google.com>
BACKGROUND
==========
When multiple work items are queued to a workqueue, their execution order
doesn't match the queueing order. They may get executed in any order and
simultaneously. When fully serialized execution - one by one in the queueing
order - is needed, an ordered workqueue should be used which can be created
with alloc_ordered_workqueue().
However, alloc_ordered_workqueue() was a later addition. Before it, an
ordered workqueue could be obtained by creating an UNBOUND workqueue with
@max_active==1. This originally was an implementation side-effect which was
broken by 4c16bd327c ("workqueue: restore WQ_UNBOUND/max_active==1 to be
ordered"). Because there were users that depended on the ordered execution,
5c0338c687 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered")
made workqueue allocation path to implicitly promote UNBOUND workqueues w/
@max_active==1 to ordered workqueues.
While this has worked okay, overloading the UNBOUND allocation interface
this way creates other issues. It's difficult to tell whether a given
workqueue actually needs to be ordered and users that legitimately want a
min concurrency level wq unexpectedly gets an ordered one instead. With
planned UNBOUND workqueue updates to improve execution locality and more
prevalence of chiplet designs which can benefit from such improvements, this
isn't a state we wanna be in forever.
This patch series audits all callsites that create an UNBOUND workqueue w/
@max_active==1 and converts them to alloc_ordered_workqueue() as necessary.
WHAT TO LOOK FOR
================
The conversions are from
alloc_workqueue(WQ_UNBOUND | flags, 1, args..)
to
alloc_ordered_workqueue(flags, args...)
which don't cause any functional changes. If you know that fully ordered
execution is not ncessary, please let me know. I'll drop the conversion and
instead add a comment noting the fact to reduce confusion while conversion
is in progress.
If you aren't fully sure, it's completely fine to let the conversion
through. The behavior will stay exactly the same and we can always
reconsider later.
As there are follow-up workqueue core changes, I'd really appreciate if the
patch can be routed through the workqueue tree w/ your acks. Thanks.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Commit e4ab08be5b ("powerpc/isa-bridge: Remove open coded "ranges"
parsing") broke PASemi Nemo board booting. The issue is the ISA I/O
range was not getting mapped as the logic to handle no "ranges" was
inverted. If phb_io_base_phys is non-zero, then the ISA range defaults
to the first 64K of the PCI I/O space. phb_io_base_phys should only be 0
when looking for a non-PCI ISA region.
Fixes: e4ab08be5b ("powerpc/isa-bridge: Remove open coded "ranges" parsing")
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Link: https://lore.kernel.org/all/301595ad-0edf-2113-b55f-f5b8051ed24c@xenosoft.de/
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230505171816.3175865-1-robh@kernel.org
- Add support for building the kernel using PC-relative addressing on Power10.
- Allow HV KVM guests on Power10 to use prefixed instructions.
- Unify support for the P2020 CPU (85xx) into a single machine description.
- Always build the 64-bit kernel with 128-bit long double.
- Drop support for several obsolete 2000's era development boards as
identified by Paul Gortmaker.
- A series fixing VFIO on Power since some generic changes.
- Various other small features and fixes.
Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Benjamin Gray, Bo Liu,
Christophe Leroy, Dan Carpenter, David Binderman, Ira Weiny, Joel Stanley,
Kajol Jain, Kautuk Consul, Liang He, Luis Chamberlain, Masahiro Yamada, Michael
Neuling, Nathan Chancellor, Nathan Lynch, Nicholas Miehlbradt, Nicholas Piggin,
Nick Desaulniers, Nysal Jan K.A, Pali Rohár, Paul Gortmaker, Paul Mackerras,
Petr Vaněk, Randy Dunlap, Rob Herring, Sachin Sant, Sean Christopherson, Segher
Boessenkool, Timothy Pearson.
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Merge tag 'powerpc-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Add support for building the kernel using PC-relative addressing on
Power10.
- Allow HV KVM guests on Power10 to use prefixed instructions.
- Unify support for the P2020 CPU (85xx) into a single machine
description.
- Always build the 64-bit kernel with 128-bit long double.
- Drop support for several obsolete 2000's era development boards as
identified by Paul Gortmaker.
- A series fixing VFIO on Power since some generic changes.
- Various other small features and fixes.
Thanks to Alexey Kardashevskiy, Andrew Donnellan, Benjamin Gray, Bo Liu,
Christophe Leroy, Dan Carpenter, David Binderman, Ira Weiny, Joel
Stanley, Kajol Jain, Kautuk Consul, Liang He, Luis Chamberlain, Masahiro
Yamada, Michael Neuling, Nathan Chancellor, Nathan Lynch, Nicholas
Miehlbradt, Nicholas Piggin, Nick Desaulniers, Nysal Jan K.A, Pali
Rohár, Paul Gortmaker, Paul Mackerras, Petr Vaněk, Randy Dunlap, Rob
Herring, Sachin Sant, Sean Christopherson, Segher Boessenkool, and
Timothy Pearson.
* tag 'powerpc-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (156 commits)
powerpc/64s: Disable pcrel code model on Clang
powerpc: Fix merge conflict between pcrel and copy_thread changes
powerpc/configs/powernv: Add IGB=y
powerpc/configs/64s: Drop JFS Filesystem
powerpc/configs/64s: Use EXT4 to mount EXT2 filesystems
powerpc/configs: Make pseries_defconfig an alias for ppc64le_guest
powerpc/configs: Make pseries_le an alias for ppc64le_guest
powerpc/configs: Incorporate generic kvm_guest.config into guest configs
powerpc/configs: Add IBMVETH=y and IBMVNIC=y to guest configs
powerpc/configs/64s: Enable Device Mapper options
powerpc/configs/64s: Enable PSTORE
powerpc/configs/64s: Enable VLAN support
powerpc/configs/64s: Enable BLK_DEV_NVME
powerpc/configs/64s: Drop REISERFS
powerpc/configs/64s: Use SHA512 for module signatures
powerpc/configs/64s: Enable IO_STRICT_DEVMEM
powerpc/configs/64s: Enable SCHEDSTATS
powerpc/configs/64s: Enable DEBUG_VM & other options
powerpc/configs/64s: Enable EMULATED_STATS
powerpc/configs/64s: Enable KUNIT and most tests
...
- Remove diagnostics and adjust config for CSD lock diagnostics
- Add a generic IPI-sending tracepoint, as currently there's no easy
way to instrument IPI origins: it's arch dependent and for some
major architectures it's not even consistently available.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'smp-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP cross-CPU function-call updates from Ingo Molnar:
- Remove diagnostics and adjust config for CSD lock diagnostics
- Add a generic IPI-sending tracepoint, as currently there's no easy
way to instrument IPI origins: it's arch dependent and for some major
architectures it's not even consistently available.
* tag 'smp-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
trace,smp: Trace all smp_function_call*() invocations
trace: Add trace_ipi_send_cpu()
sched, smp: Trace smp callback causing an IPI
smp: reword smp call IPI comment
treewide: Trace IPIs sent via smp_send_reschedule()
irq_work: Trace self-IPIs sent via arch_irq_work_raise()
smp: Trace IPIs sent via arch_send_call_function_ipi_mask()
sched, smp: Trace IPIs sent via send_call_function_single_ipi()
trace: Add trace_ipi_send_cpumask()
kernel/smp: Make csdlock_debug= resettable
locking/csd_lock: Remove per-CPU data indirection from CSD lock debugging
locking/csd_lock: Remove added data from CSD lock debugging
locking/csd_lock: Add Kconfig option for csd_debug default
- Mark arch_cpu_idle_dead() __noreturn, make all architectures & drivers that did
this inconsistently follow this new, common convention, and fix all the fallout
that objtool can now detect statically.
- Fix/improve the ORC unwinder becoming unreliable due to UNWIND_HINT_EMPTY ambiguity,
split it into UNWIND_HINT_END_OF_STACK and UNWIND_HINT_UNDEFINED to resolve it.
- Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code.
- Generate ORC data for __pfx code
- Add more __noreturn annotations to various kernel startup/shutdown/panic functions.
- Misc improvements & fixes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
- Mark arch_cpu_idle_dead() __noreturn, make all architectures &
drivers that did this inconsistently follow this new, common
convention, and fix all the fallout that objtool can now detect
statically
- Fix/improve the ORC unwinder becoming unreliable due to
UNWIND_HINT_EMPTY ambiguity, split it into UNWIND_HINT_END_OF_STACK
and UNWIND_HINT_UNDEFINED to resolve it
- Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code
- Generate ORC data for __pfx code
- Add more __noreturn annotations to various kernel startup/shutdown
and panic functions
- Misc improvements & fixes
* tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
x86/hyperv: Mark hv_ghcb_terminate() as noreturn
scsi: message: fusion: Mark mpt_halt_firmware() __noreturn
x86/cpu: Mark {hlt,resume}_play_dead() __noreturn
btrfs: Mark btrfs_assertfail() __noreturn
objtool: Include weak functions in global_noreturns check
cpu: Mark nmi_panic_self_stop() __noreturn
cpu: Mark panic_smp_self_stop() __noreturn
arm64/cpu: Mark cpu_park_loop() and friends __noreturn
x86/head: Mark *_start_kernel() __noreturn
init: Mark start_kernel() __noreturn
init: Mark [arch_call_]rest_init() __noreturn
objtool: Generate ORC data for __pfx code
x86/linkage: Fix padding for typed functions
objtool: Separate prefix code from stack validation code
objtool: Remove superfluous dead_end_function() check
objtool: Add symbol iteration helpers
objtool: Add WARN_INSN()
scripts/objdump-func: Support multiple functions
context_tracking: Fix KCSAN noinstr violation
objtool: Add stackleak instrumentation to uaccess safe list
...
switching from a user process to a kernel thread.
- More folio conversions from Kefeng Wang, Zhang Peng and Pankaj Raghav.
- zsmalloc performance improvements from Sergey Senozhatsky.
- Yue Zhao has found and fixed some data race issues around the
alteration of memcg userspace tunables.
- VFS rationalizations from Christoph Hellwig:
- removal of most of the callers of write_one_page().
- make __filemap_get_folio()'s return value more useful
- Luis Chamberlain has changed tmpfs so it no longer requires swap
backing. Use `mount -o noswap'.
- Qi Zheng has made the slab shrinkers operate locklessly, providing
some scalability benefits.
- Keith Busch has improved dmapool's performance, making part of its
operations O(1) rather than O(n).
- Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
permitting userspace to wr-protect anon memory unpopulated ptes.
- Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive rather
than exclusive, and has fixed a bunch of errors which were caused by its
unintuitive meaning.
- Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
which causes minor faults to install a write-protected pte.
- Vlastimil Babka has done some maintenance work on vma_merge():
cleanups to the kernel code and improvements to our userspace test
harness.
- Cleanups to do_fault_around() by Lorenzo Stoakes.
- Mike Rapoport has moved a lot of initialization code out of various
mm/ files and into mm/mm_init.c.
- Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
DRM, but DRM doesn't use it any more.
- Lorenzo has also coverted read_kcore() and vread() to use iterators
and has thereby removed the use of bounce buffers in some cases.
- Lorenzo has also contributed further cleanups of vma_merge().
- Chaitanya Prakash provides some fixes to the mmap selftesting code.
- Matthew Wilcox changes xfs and afs so they no longer take sleeping
locks in ->map_page(), a step towards RCUification of pagefaults.
- Suren Baghdasaryan has improved mmap_lock scalability by switching to
per-VMA locking.
- Frederic Weisbecker has reworked the percpu cache draining so that it
no longer causes latency glitches on cpu isolated workloads.
- Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
logic.
- Liu Shixin has changed zswap's initialization so we no longer waste a
chunk of memory if zswap is not being used.
- Yosry Ahmed has improved the performance of memcg statistics flushing.
- David Stevens has fixed several issues involving khugepaged,
userfaultfd and shmem.
- Christoph Hellwig has provided some cleanup work to zram's IO-related
code paths.
- David Hildenbrand has fixed up some issues in the selftest code's
testing of our pte state changing.
- Pankaj Raghav has made page_endio() unneeded and has removed it.
- Peter Xu contributed some rationalizations of the userfaultfd
selftests.
- Yosry Ahmed has fixed an issue around memcg's page recalim accounting.
- Chaitanya Prakash has fixed some arm-related issues in the
selftests/mm code.
- Longlong Xia has improved the way in which KSM handles hwpoisoned
pages.
- Peter Xu fixes a few issues with uffd-wp at fork() time.
- Stefan Roesch has changed KSM so that it may now be used on a
per-process and per-cgroup basis.
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Merge tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
switching from a user process to a kernel thread.
- More folio conversions from Kefeng Wang, Zhang Peng and Pankaj
Raghav.
- zsmalloc performance improvements from Sergey Senozhatsky.
- Yue Zhao has found and fixed some data race issues around the
alteration of memcg userspace tunables.
- VFS rationalizations from Christoph Hellwig:
- removal of most of the callers of write_one_page()
- make __filemap_get_folio()'s return value more useful
- Luis Chamberlain has changed tmpfs so it no longer requires swap
backing. Use `mount -o noswap'.
- Qi Zheng has made the slab shrinkers operate locklessly, providing
some scalability benefits.
- Keith Busch has improved dmapool's performance, making part of its
operations O(1) rather than O(n).
- Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
permitting userspace to wr-protect anon memory unpopulated ptes.
- Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive
rather than exclusive, and has fixed a bunch of errors which were
caused by its unintuitive meaning.
- Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
which causes minor faults to install a write-protected pte.
- Vlastimil Babka has done some maintenance work on vma_merge():
cleanups to the kernel code and improvements to our userspace test
harness.
- Cleanups to do_fault_around() by Lorenzo Stoakes.
- Mike Rapoport has moved a lot of initialization code out of various
mm/ files and into mm/mm_init.c.
- Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
DRM, but DRM doesn't use it any more.
- Lorenzo has also coverted read_kcore() and vread() to use iterators
and has thereby removed the use of bounce buffers in some cases.
- Lorenzo has also contributed further cleanups of vma_merge().
- Chaitanya Prakash provides some fixes to the mmap selftesting code.
- Matthew Wilcox changes xfs and afs so they no longer take sleeping
locks in ->map_page(), a step towards RCUification of pagefaults.
- Suren Baghdasaryan has improved mmap_lock scalability by switching to
per-VMA locking.
- Frederic Weisbecker has reworked the percpu cache draining so that it
no longer causes latency glitches on cpu isolated workloads.
- Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
logic.
- Liu Shixin has changed zswap's initialization so we no longer waste a
chunk of memory if zswap is not being used.
- Yosry Ahmed has improved the performance of memcg statistics
flushing.
- David Stevens has fixed several issues involving khugepaged,
userfaultfd and shmem.
- Christoph Hellwig has provided some cleanup work to zram's IO-related
code paths.
- David Hildenbrand has fixed up some issues in the selftest code's
testing of our pte state changing.
- Pankaj Raghav has made page_endio() unneeded and has removed it.
- Peter Xu contributed some rationalizations of the userfaultfd
selftests.
- Yosry Ahmed has fixed an issue around memcg's page recalim
accounting.
- Chaitanya Prakash has fixed some arm-related issues in the
selftests/mm code.
- Longlong Xia has improved the way in which KSM handles hwpoisoned
pages.
- Peter Xu fixes a few issues with uffd-wp at fork() time.
- Stefan Roesch has changed KSM so that it may now be used on a
per-process and per-cgroup basis.
* tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
mm,unmap: avoid flushing TLB in batch if PTE is inaccessible
shmem: restrict noswap option to initial user namespace
mm/khugepaged: fix conflicting mods to collapse_file()
sparse: remove unnecessary 0 values from rc
mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area()
hugetlb: pte_alloc_huge() to replace huge pte_alloc_map()
maple_tree: fix allocation in mas_sparse_area()
mm: do not increment pgfault stats when page fault handler retries
zsmalloc: allow only one active pool compaction context
selftests/mm: add new selftests for KSM
mm: add new KSM process and sysfs knobs
mm: add new api to enable ksm per process
mm: shrinkers: fix debugfs file permissions
mm: don't check VMA write permissions if the PTE/PMD indicates write permissions
migrate_pages_batch: fix statistics for longterm pin retry
userfaultfd: use helper function range_in_vma()
lib/show_mem.c: use for_each_populated_zone() simplify code
mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list()
fs/buffer: convert create_page_buffers to folio_create_buffers
fs/buffer: add folio_create_empty_buffers helper
...
The summary of the changes for this pull requests is:
* Song Liu's new struct module_memory replacement
* Nick Alcock's MODULE_LICENSE() removal for non-modules
* My cleanups and enhancements to reduce the areas where we vmalloc
module memory for duplicates, and the respective debug code which
proves the remaining vmalloc pressure comes from userspace.
Most of the changes have been in linux-next for quite some time except
the minor fixes I made to check if a module was already loaded
prior to allocating the final module memory with vmalloc and the
respective debug code it introduces to help clarify the issue. Although
the functional change is small it is rather safe as it can only *help*
reduce vmalloc space for duplicates and is confirmed to fix a bootup
issue with over 400 CPUs with KASAN enabled. I don't expect stable
kernels to pick up that fix as the cleanups would have also had to have
been picked up. Folks on larger CPU systems with modules will want to
just upgrade if vmalloc space has been an issue on bootup.
Given the size of this request, here's some more elaborate details
on this pull request.
The functional change change in this pull request is the very first
patch from Song Liu which replaces the struct module_layout with a new
struct module memory. The old data structure tried to put together all
types of supported module memory types in one data structure, the new
one abstracts the differences in memory types in a module to allow each
one to provide their own set of details. This paves the way in the
future so we can deal with them in a cleaner way. If you look at changes
they also provide a nice cleanup of how we handle these different memory
areas in a module. This change has been in linux-next since before the
merge window opened for v6.3 so to provide more than a full kernel cycle
of testing. It's a good thing as quite a bit of fixes have been found
for it.
Jason Baron then made dynamic debug a first class citizen module user by
using module notifier callbacks to allocate / remove module specific
dynamic debug information.
Nick Alcock has done quite a bit of work cross-tree to remove module
license tags from things which cannot possibly be module at my request
so to:
a) help him with his longer term tooling goals which require a
deterministic evaluation if a piece a symbol code could ever be
part of a module or not. But quite recently it is has been made
clear that tooling is not the only one that would benefit.
Disambiguating symbols also helps efforts such as live patching,
kprobes and BPF, but for other reasons and R&D on this area
is active with no clear solution in sight.
b) help us inch closer to the now generally accepted long term goal
of automating all the MODULE_LICENSE() tags from SPDX license tags
In so far as a) is concerned, although module license tags are a no-op
for non-modules, tools which would want create a mapping of possible
modules can only rely on the module license tag after the commit
8b41fc4454 ("kbuild: create modules.builtin without Makefile.modbuiltin
or tristate.conf"). Nick has been working on this *for years* and
AFAICT I was the only one to suggest two alternatives to this approach
for tooling. The complexity in one of my suggested approaches lies in
that we'd need a possible-obj-m and a could-be-module which would check
if the object being built is part of any kconfig build which could ever
lead to it being part of a module, and if so define a new define
-DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've
suggested would be to have a tristate in kconfig imply the same new
-DPOSSIBLE_MODULE as well but that means getting kconfig symbol names
mapping to modules always, and I don't think that's the case today. I am
not aware of Nick or anyone exploring either of these options. Quite
recently Josh Poimboeuf has pointed out that live patching, kprobes and
BPF would benefit from resolving some part of the disambiguation as
well but for other reasons. The function granularity KASLR (fgkaslr)
patches were mentioned but Joe Lawrence has clarified this effort has
been dropped with no clear solution in sight [1].
In the meantime removing module license tags from code which could never
be modules is welcomed for both objectives mentioned above. Some
developers have also welcomed these changes as it has helped clarify
when a module was never possible and they forgot to clean this up,
and so you'll see quite a bit of Nick's patches in other pull
requests for this merge window. I just picked up the stragglers after
rc3. LWN has good coverage on the motivation behind this work [2] and
the typical cross-tree issues he ran into along the way. The only
concrete blocker issue he ran into was that we should not remove the
MODULE_LICENSE() tags from files which have no SPDX tags yet, even if
they can never be modules. Nick ended up giving up on his efforts due
to having to do this vetting and backlash he ran into from folks who
really did *not understand* the core of the issue nor were providing
any alternative / guidance. I've gone through his changes and dropped
the patches which dropped the module license tags where an SPDX
license tag was missing, it only consisted of 11 drivers. To see
if a pull request deals with a file which lacks SPDX tags you
can just use:
./scripts/spdxcheck.py -f \
$(git diff --name-only commid-id | xargs echo)
You'll see a core module file in this pull request for the above,
but that's not related to his changes. WE just need to add the SPDX
license tag for the kernel/module/kmod.c file in the future but
it demonstrates the effectiveness of the script.
Most of Nick's changes were spread out through different trees,
and I just picked up the slack after rc3 for the last kernel was out.
Those changes have been in linux-next for over two weeks.
The cleanups, debug code I added and final fix I added for modules
were motivated by David Hildenbrand's report of boot failing on
a systems with over 400 CPUs when KASAN was enabled due to running
out of virtual memory space. Although the functional change only
consists of 3 lines in the patch "module: avoid allocation if module is
already present and ready", proving that this was the best we can
do on the modules side took quite a bit of effort and new debug code.
The initial cleanups I did on the modules side of things has been
in linux-next since around rc3 of the last kernel, the actual final
fix for and debug code however have only been in linux-next for about a
week or so but I think it is worth getting that code in for this merge
window as it does help fix / prove / evaluate the issues reported
with larger number of CPUs. Userspace is not yet fixed as it is taking
a bit of time for folks to understand the crux of the issue and find a
proper resolution. Worst come to worst, I have a kludge-of-concept [3]
of how to make kernel_read*() calls for modules unique / converge them,
but I'm currently inclined to just see if userspace can fix this
instead.
[0] https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/
[1] https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com
[2] https://lwn.net/Articles/927569/
[3] https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org
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Merge tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull module updates from Luis Chamberlain:
"The summary of the changes for this pull requests is:
- Song Liu's new struct module_memory replacement
- Nick Alcock's MODULE_LICENSE() removal for non-modules
- My cleanups and enhancements to reduce the areas where we vmalloc
module memory for duplicates, and the respective debug code which
proves the remaining vmalloc pressure comes from userspace.
Most of the changes have been in linux-next for quite some time except
the minor fixes I made to check if a module was already loaded prior
to allocating the final module memory with vmalloc and the respective
debug code it introduces to help clarify the issue. Although the
functional change is small it is rather safe as it can only *help*
reduce vmalloc space for duplicates and is confirmed to fix a bootup
issue with over 400 CPUs with KASAN enabled. I don't expect stable
kernels to pick up that fix as the cleanups would have also had to
have been picked up. Folks on larger CPU systems with modules will
want to just upgrade if vmalloc space has been an issue on bootup.
Given the size of this request, here's some more elaborate details:
The functional change change in this pull request is the very first
patch from Song Liu which replaces the 'struct module_layout' with a
new 'struct module_memory'. The old data structure tried to put
together all types of supported module memory types in one data
structure, the new one abstracts the differences in memory types in a
module to allow each one to provide their own set of details. This
paves the way in the future so we can deal with them in a cleaner way.
If you look at changes they also provide a nice cleanup of how we
handle these different memory areas in a module. This change has been
in linux-next since before the merge window opened for v6.3 so to
provide more than a full kernel cycle of testing. It's a good thing as
quite a bit of fixes have been found for it.
Jason Baron then made dynamic debug a first class citizen module user
by using module notifier callbacks to allocate / remove module
specific dynamic debug information.
Nick Alcock has done quite a bit of work cross-tree to remove module
license tags from things which cannot possibly be module at my request
so to:
a) help him with his longer term tooling goals which require a
deterministic evaluation if a piece a symbol code could ever be
part of a module or not. But quite recently it is has been made
clear that tooling is not the only one that would benefit.
Disambiguating symbols also helps efforts such as live patching,
kprobes and BPF, but for other reasons and R&D on this area is
active with no clear solution in sight.
b) help us inch closer to the now generally accepted long term goal
of automating all the MODULE_LICENSE() tags from SPDX license tags
In so far as a) is concerned, although module license tags are a no-op
for non-modules, tools which would want create a mapping of possible
modules can only rely on the module license tag after the commit
8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf").
Nick has been working on this *for years* and AFAICT I was the only
one to suggest two alternatives to this approach for tooling. The
complexity in one of my suggested approaches lies in that we'd need a
possible-obj-m and a could-be-module which would check if the object
being built is part of any kconfig build which could ever lead to it
being part of a module, and if so define a new define
-DPOSSIBLE_MODULE [0].
A more obvious yet theoretical approach I've suggested would be to
have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as
well but that means getting kconfig symbol names mapping to modules
always, and I don't think that's the case today. I am not aware of
Nick or anyone exploring either of these options. Quite recently Josh
Poimboeuf has pointed out that live patching, kprobes and BPF would
benefit from resolving some part of the disambiguation as well but for
other reasons. The function granularity KASLR (fgkaslr) patches were
mentioned but Joe Lawrence has clarified this effort has been dropped
with no clear solution in sight [1].
In the meantime removing module license tags from code which could
never be modules is welcomed for both objectives mentioned above. Some
developers have also welcomed these changes as it has helped clarify
when a module was never possible and they forgot to clean this up, and
so you'll see quite a bit of Nick's patches in other pull requests for
this merge window. I just picked up the stragglers after rc3. LWN has
good coverage on the motivation behind this work [2] and the typical
cross-tree issues he ran into along the way. The only concrete blocker
issue he ran into was that we should not remove the MODULE_LICENSE()
tags from files which have no SPDX tags yet, even if they can never be
modules. Nick ended up giving up on his efforts due to having to do
this vetting and backlash he ran into from folks who really did *not
understand* the core of the issue nor were providing any alternative /
guidance. I've gone through his changes and dropped the patches which
dropped the module license tags where an SPDX license tag was missing,
it only consisted of 11 drivers. To see if a pull request deals with a
file which lacks SPDX tags you can just use:
./scripts/spdxcheck.py -f \
$(git diff --name-only commid-id | xargs echo)
You'll see a core module file in this pull request for the above, but
that's not related to his changes. WE just need to add the SPDX
license tag for the kernel/module/kmod.c file in the future but it
demonstrates the effectiveness of the script.
Most of Nick's changes were spread out through different trees, and I
just picked up the slack after rc3 for the last kernel was out. Those
changes have been in linux-next for over two weeks.
The cleanups, debug code I added and final fix I added for modules
were motivated by David Hildenbrand's report of boot failing on a
systems with over 400 CPUs when KASAN was enabled due to running out
of virtual memory space. Although the functional change only consists
of 3 lines in the patch "module: avoid allocation if module is already
present and ready", proving that this was the best we can do on the
modules side took quite a bit of effort and new debug code.
The initial cleanups I did on the modules side of things has been in
linux-next since around rc3 of the last kernel, the actual final fix
for and debug code however have only been in linux-next for about a
week or so but I think it is worth getting that code in for this merge
window as it does help fix / prove / evaluate the issues reported with
larger number of CPUs. Userspace is not yet fixed as it is taking a
bit of time for folks to understand the crux of the issue and find a
proper resolution. Worst come to worst, I have a kludge-of-concept [3]
of how to make kernel_read*() calls for modules unique / converge
them, but I'm currently inclined to just see if userspace can fix this
instead"
Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0]
Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1]
Link: https://lwn.net/Articles/927569/ [2]
Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3]
* tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits)
module: add debugging auto-load duplicate module support
module: stats: fix invalid_mod_bytes typo
module: remove use of uninitialized variable len
module: fix building stats for 32-bit targets
module: stats: include uapi/linux/module.h
module: avoid allocation if module is already present and ready
module: add debug stats to help identify memory pressure
module: extract patient module check into helper
modules/kmod: replace implementation with a semaphore
Change DEFINE_SEMAPHORE() to take a number argument
module: fix kmemleak annotations for non init ELF sections
module: Ignore L0 and rename is_arm_mapping_symbol()
module: Move is_arm_mapping_symbol() to module_symbol.h
module: Sync code of is_arm_mapping_symbol()
scripts/gdb: use mem instead of core_layout to get the module address
interconnect: remove module-related code
interconnect: remove MODULE_LICENSE in non-modules
zswap: remove MODULE_LICENSE in non-modules
zpool: remove MODULE_LICENSE in non-modules
x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules
...
Here is the large set of driver core changes for 6.4-rc1.
Once again, a busy development cycle, with lots of changes happening in
the driver core in the quest to be able to move "struct bus" and "struct
class" into read-only memory, a task now complete with these changes.
This will make the future rust interactions with the driver core more
"provably correct" as well as providing more obvious lifetime rules for
all busses and classes in the kernel.
The changes required for this did touch many individual classes and
busses as many callbacks were changed to take const * parameters
instead. All of these changes have been submitted to the various
subsystem maintainers, giving them plenty of time to review, and most of
them actually did so.
Other than those changes, included in here are a small set of other
things:
- kobject logging improvements
- cacheinfo improvements and updates
- obligatory fw_devlink updates and fixes
- documentation updates
- device property cleanups and const * changes
- firwmare loader dependency fixes.
All of these have been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the large set of driver core changes for 6.4-rc1.
Once again, a busy development cycle, with lots of changes happening
in the driver core in the quest to be able to move "struct bus" and
"struct class" into read-only memory, a task now complete with these
changes.
This will make the future rust interactions with the driver core more
"provably correct" as well as providing more obvious lifetime rules
for all busses and classes in the kernel.
The changes required for this did touch many individual classes and
busses as many callbacks were changed to take const * parameters
instead. All of these changes have been submitted to the various
subsystem maintainers, giving them plenty of time to review, and most
of them actually did so.
Other than those changes, included in here are a small set of other
things:
- kobject logging improvements
- cacheinfo improvements and updates
- obligatory fw_devlink updates and fixes
- documentation updates
- device property cleanups and const * changes
- firwmare loader dependency fixes.
All of these have been in linux-next for a while with no reported
problems"
* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
device property: make device_property functions take const device *
driver core: update comments in device_rename()
driver core: Don't require dynamic_debug for initcall_debug probe timing
firmware_loader: rework crypto dependencies
firmware_loader: Strip off \n from customized path
zram: fix up permission for the hot_add sysfs file
cacheinfo: Add use_arch[|_cache]_info field/function
arch_topology: Remove early cacheinfo error message if -ENOENT
cacheinfo: Check cache properties are present in DT
cacheinfo: Check sib_leaf in cache_leaves_are_shared()
cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
cacheinfo: Add arm64 early level initializer implementation
cacheinfo: Add arch specific early level initializer
tty: make tty_class a static const structure
driver core: class: remove struct class_interface * from callbacks
driver core: class: mark the struct class in struct class_interface constant
driver core: class: make class_register() take a const *
driver core: class: mark class_release() as taking a const *
driver core: remove incorrect comment for device_create*
MIPS: vpe-cmp: remove module owner pointer from struct class usage.
...
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Merge tag 'pci-v6.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull pci updates from Bjorn Helgaas:
"Resource management:
- Add pci_dev_for_each_resource() and pci_bus_for_each_resource()
iterators
PCIe native device hotplug:
- Fix AB-BA deadlock between reset_lock and device_lock
Power management:
- Wait longer for devices to become ready after resume (as we do for
reset) to accommodate Intel Titan Ridge xHCI devices
- Extend D3hot delay for NVIDIA HDA controllers to avoid
unrecoverable devices after a bus reset
Error handling:
- Clear PCIe Device Status after EDR since generic error recovery now
only clears it when AER is native
ASPM:
- Work around Chromebook firmware defect that clobbers Capability
list (including ASPM L1 PM Substates Cap) when returning from
D3cold to D0
Freescale i.MX6 PCIe controller driver:
- Install imprecise external abort handler only when DT indicates
PCIe support
Freescale Layerscape PCIe controller driver:
- Add ls1028a endpoint mode support
Qualcomm PCIe controller driver:
- Add SM8550 DT binding and driver support
- Add SDX55 DT binding and driver support
- Use bulk APIs for clocks of IP 1.0.0, 2.3.2, 2.3.3
- Use bulk APIs for reset of IP 2.1.0, 2.3.3, 2.4.0
- Add DT "mhi" register region for supported SoCs
- Expose link transition counts via debugfs to help debug low power
issues
- Support system suspend and resume; reduce interconnect bandwidth
and turn off clock and PHY if there are no active devices
- Enable async probe by default to reduce boot time
Miscellaneous:
- Sort controller Kconfig entries by vendor"
* tag 'pci-v6.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (56 commits)
PCI: xilinx: Drop obsolete dependency on COMPILE_TEST
PCI: mobiveil: Sort Kconfig entries by vendor
PCI: dwc: Sort Kconfig entries by vendor
PCI: Sort controller Kconfig entries by vendor
PCI: Use consistent controller Kconfig menu entry language
PCI: xilinx-nwl: Add 'Xilinx' to Kconfig prompt
PCI: hv: Add 'Microsoft' to Kconfig prompt
PCI: meson: Add 'Amlogic' to Kconfig prompt
PCI: Use of_property_present() for testing DT property presence
PCI/PM: Extend D3hot delay for NVIDIA HDA controllers
dt-bindings: PCI: qcom: Document msi-map and msi-map-mask properties
PCI: qcom: Add SM8550 PCIe support
dt-bindings: PCI: qcom: Add SM8550 compatible
PCI: qcom: Add support for SDX55 SoC
dt-bindings: PCI: qcom-ep: Fix the unit address used in example
dt-bindings: PCI: qcom: Add SDX55 SoC
dt-bindings: PCI: qcom: Update maintainers entry
PCI: qcom: Enable async probe by default
PCI: qcom: Add support for system suspend and resume
PCI/PM: Drop pci_bridge_wait_for_secondary_bus() timeout parameter
...
- Improve the VDSO build time checks to cover all dynamic relocations
VDSO does not allow dynamic relcations, but the build time check is
incomplete and fragile.
It's based on architectures specifying the relocation types to search
for and does not handle R_*_NONE relocation entries correctly.
R_*_NONE relocations are injected by some GNU ld variants if they fail
to determine the exact .rel[a]/dyn_size to cover trailing zeros.
R_*_NONE relocations must be ignored by dynamic loaders, so they
should be ignored in the build time check too.
Remove the architecture specific relocation types to check for and
validate strictly that no other relocations than R_*_NONE end up
in the VSDO .so file.
- Prefer signal delivery to the current thread for
CLOCK_PROCESS_CPUTIME_ID based posix-timers
Such timers prefer to deliver the signal to the main thread of a
process even if the context in which the timer expires is the current
task. This has the downside that it might wake up an idle thread.
As there is no requirement or guarantee that the signal has to be
delivered to the main thread, avoid this by preferring the current
task if it is part of the thread group which shares sighand.
This not only avoids waking idle threads, it also distributes the
signal delivery in case of multiple timers firing in the context
of different threads close to each other better.
- Align the tick period properly (again)
For a long time the tick was starting at CLOCK_MONOTONIC zero, which
allowed users space applications to either align with the tick or to
place a periodic computation so that it does not interfere with the
tick. The alignement of the tick period was more by chance than by
intention as the tick is set up before a high resolution clocksource is
installed, i.e. timekeeping is still tick based and the tick period
advances from there.
The early enablement of sched_clock() broke this alignement as the time
accumulated by sched_clock() is taken into account when timekeeping is
initialized. So the base value now(CLOCK_MONOTONIC) is not longer a
multiple of tick periods, which breaks applications which relied on
that behaviour.
Cure this by aligning the tick starting point to the next multiple of
tick periods, i.e 1000ms/CONFIG_HZ.
- A set of NOHZ fixes and enhancements
- Cure the concurrent writer race for idle and IO sleeptime statistics
The statitic values which are exposed via /proc/stat are updated from
the CPU local idle exit and remotely by cpufreq, but that happens
without any form of serialization. As a consequence sleeptimes can be
accounted twice or worse.
Prevent this by restricting the accumulation writeback to the CPU
local idle exit and let the remote access compute the accumulated
value.
- Protect idle/iowait sleep time with a sequence count
Reading idle/iowait sleep time, e.g. from /proc/stat, can race with
idle exit updates. As a consequence the readout may result in random
and potentially going backwards values.
Protect this by a sequence count, which fixes the idle time
statistics issue, but cannot fix the iowait time problem because
iowait time accounting races with remote wake ups decrementing the
remote runqueues nr_iowait counter. The latter is impossible to fix,
so the only way to deal with that is to document it properly and to
remove the assertion in the selftest which triggers occasionally due
to that.
- Restructure struct tick_sched for better cache layout
- Some small cleanups and a better cache layout for struct tick_sched
- Implement the missing timer_wait_running() callback for POSIX CPU timers
For unknown reason the introduction of the timer_wait_running() callback
missed to fixup posix CPU timers, which went unnoticed for almost four
years.
While initially only targeted to prevent livelocks between a timer
deletion and the timer expiry function on PREEMPT_RT enabled kernels, it
turned out that fixing this for mainline is not as trivial as just
implementing a stub similar to the hrtimer/timer callbacks.
The reason is that for CONFIG_POSIX_CPU_TIMERS_TASK_WORK enabled systems
there is a livelock issue independent of RT.
CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y moves the expiry of POSIX CPU timers
out from hard interrupt context to task work, which is handled before
returning to user space or to a VM. The expiry mechanism moves the
expired timers to a stack local list head with sighand lock held. Once
sighand is dropped the task can be preempted and a task which wants to
delete a timer will spin-wait until the expiry task is scheduled back
in. In the worst case this will end up in a livelock when the preempting
task and the expiry task are pinned on the same CPU.
The timer wheel has a timer_wait_running() mechanism for RT, which uses
a per CPU timer-base expiry lock which is held by the expiry code and the
task waiting for the timer function to complete blocks on that lock.
This does not work in the same way for posix CPU timers as there is no
timer base and expiry for process wide timers can run on any task
belonging to that process, but the concept of waiting on an expiry lock
can be used too in a slightly different way.
Add a per task mutex to struct posix_cputimers_work, let the expiry task
hold it accross the expiry function and let the deleting task which
waits for the expiry to complete block on the mutex.
In the non-contended case this results in an extra mutex_lock()/unlock()
pair on both sides.
This avoids spin-waiting on a task which is scheduled out, prevents the
livelock and cures the problem for RT and !RT systems.
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Merge tag 'timers-core-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timers and timekeeping updates from Thomas Gleixner:
- Improve the VDSO build time checks to cover all dynamic relocations
VDSO does not allow dynamic relocations, but the build time check is
incomplete and fragile.
It's based on architectures specifying the relocation types to search
for and does not handle R_*_NONE relocation entries correctly.
R_*_NONE relocations are injected by some GNU ld variants if they
fail to determine the exact .rel[a]/dyn_size to cover trailing zeros.
R_*_NONE relocations must be ignored by dynamic loaders, so they
should be ignored in the build time check too.
Remove the architecture specific relocation types to check for and
validate strictly that no other relocations than R_*_NONE end up in
the VSDO .so file.
- Prefer signal delivery to the current thread for
CLOCK_PROCESS_CPUTIME_ID based posix-timers
Such timers prefer to deliver the signal to the main thread of a
process even if the context in which the timer expires is the current
task. This has the downside that it might wake up an idle thread.
As there is no requirement or guarantee that the signal has to be
delivered to the main thread, avoid this by preferring the current
task if it is part of the thread group which shares sighand.
This not only avoids waking idle threads, it also distributes the
signal delivery in case of multiple timers firing in the context of
different threads close to each other better.
- Align the tick period properly (again)
For a long time the tick was starting at CLOCK_MONOTONIC zero, which
allowed users space applications to either align with the tick or to
place a periodic computation so that it does not interfere with the
tick. The alignement of the tick period was more by chance than by
intention as the tick is set up before a high resolution clocksource
is installed, i.e. timekeeping is still tick based and the tick
period advances from there.
The early enablement of sched_clock() broke this alignement as the
time accumulated by sched_clock() is taken into account when
timekeeping is initialized. So the base value now(CLOCK_MONOTONIC) is
not longer a multiple of tick periods, which breaks applications
which relied on that behaviour.
Cure this by aligning the tick starting point to the next multiple of
tick periods, i.e 1000ms/CONFIG_HZ.
- A set of NOHZ fixes and enhancements:
* Cure the concurrent writer race for idle and IO sleeptime
statistics
The statitic values which are exposed via /proc/stat are updated
from the CPU local idle exit and remotely by cpufreq, but that
happens without any form of serialization. As a consequence
sleeptimes can be accounted twice or worse.
Prevent this by restricting the accumulation writeback to the CPU
local idle exit and let the remote access compute the accumulated
value.
* Protect idle/iowait sleep time with a sequence count
Reading idle/iowait sleep time, e.g. from /proc/stat, can race
with idle exit updates. As a consequence the readout may result
in random and potentially going backwards values.
Protect this by a sequence count, which fixes the idle time
statistics issue, but cannot fix the iowait time problem because
iowait time accounting races with remote wake ups decrementing
the remote runqueues nr_iowait counter. The latter is impossible
to fix, so the only way to deal with that is to document it
properly and to remove the assertion in the selftest which
triggers occasionally due to that.
* Restructure struct tick_sched for better cache layout
* Some small cleanups and a better cache layout for struct
tick_sched
- Implement the missing timer_wait_running() callback for POSIX CPU
timers
For unknown reason the introduction of the timer_wait_running()
callback missed to fixup posix CPU timers, which went unnoticed for
almost four years.
While initially only targeted to prevent livelocks between a timer
deletion and the timer expiry function on PREEMPT_RT enabled kernels,
it turned out that fixing this for mainline is not as trivial as just
implementing a stub similar to the hrtimer/timer callbacks.
The reason is that for CONFIG_POSIX_CPU_TIMERS_TASK_WORK enabled
systems there is a livelock issue independent of RT.
CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y moves the expiry of POSIX CPU
timers out from hard interrupt context to task work, which is handled
before returning to user space or to a VM. The expiry mechanism moves
the expired timers to a stack local list head with sighand lock held.
Once sighand is dropped the task can be preempted and a task which
wants to delete a timer will spin-wait until the expiry task is
scheduled back in. In the worst case this will end up in a livelock
when the preempting task and the expiry task are pinned on the same
CPU.
The timer wheel has a timer_wait_running() mechanism for RT, which
uses a per CPU timer-base expiry lock which is held by the expiry
code and the task waiting for the timer function to complete blocks
on that lock.
This does not work in the same way for posix CPU timers as there is
no timer base and expiry for process wide timers can run on any task
belonging to that process, but the concept of waiting on an expiry
lock can be used too in a slightly different way.
Add a per task mutex to struct posix_cputimers_work, let the expiry
task hold it accross the expiry function and let the deleting task
which waits for the expiry to complete block on the mutex.
In the non-contended case this results in an extra
mutex_lock()/unlock() pair on both sides.
This avoids spin-waiting on a task which is scheduled out, prevents
the livelock and cures the problem for RT and !RT systems
* tag 'timers-core-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
posix-cpu-timers: Implement the missing timer_wait_running callback
selftests/proc: Assert clock_gettime(CLOCK_BOOTTIME) VS /proc/uptime monotonicity
selftests/proc: Remove idle time monotonicity assertions
MAINTAINERS: Remove stale email address
timers/nohz: Remove middle-function __tick_nohz_idle_stop_tick()
timers/nohz: Add a comment about broken iowait counter update race
timers/nohz: Protect idle/iowait sleep time under seqcount
timers/nohz: Only ever update sleeptime from idle exit
timers/nohz: Restructure and reshuffle struct tick_sched
tick/common: Align tick period with the HZ tick.
selftests/timers/posix_timers: Test delivery of signals across threads
posix-timers: Prefer delivery of signals to the current thread
vdso: Improve cmd_vdso_check to check all dynamic relocations
Since commit a01353cf18 ("cpuidle: Fix ct_idle_*() usage"), the
cpuidle entry code calls trace_hardirqs_on() (actually
trace_hardirqs_on_prepare()) in ct_cpuidle_enter() before calling into
the cpuidle driver.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406144535.3786008-2-mpe@ellerman.id.au
Code in the idle path is not allowed to be instrumented because RCU is
disabled, see commit 0e985e9d22 ("cpuidle: Add comments about
noinstr/__cpuidle usage").
Mark prep_irq_for_idle() __cpuidle, which is equivalent to noinstr, to
enforce that.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406144535.3786008-1-mpe@ellerman.id.au
Build modules using PCREL addressing when CONFIG_PPC_KERNEL_PCREL=y.
- The module loader must handle several new relocation types:
* R_PPC64_REL24_NOTOC is a function call handled like R_PPC_REL24, but
does not restore r2 upon return. The external function call stub is
changed to use pcrel addressing to load the function pointer rather
than based on the module TOC.
* R_PPC64_GOT_PCREL34 is a reference to external data. A GOT table
must be built by hand, because the linker adds this during the final
link (which is not done for kernel modules). The GOT table is built
similarly to the way the external function call stub table is. This
section is called .mygot because .got has a special meaning for the
linker and can become upset.
* R_PPC64_PCREL34 is used for local data addressing, but there is a
special case where the percpu section is moved at load-time to the
percpu area which is out of range of this relocation. This requires
the PCREL34 relocations are converted to use GOT_PCREL34 addressing.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Some coding style & formatting fixups]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-7-npiggin@gmail.com
PC-Relative or PCREL addressing is an extension to the ELF ABI which
uses Power ISA v3.1 PC-relative instructions to calculate addresses,
rather than the traditional TOC scheme.
Add an option to build vmlinux using pcrel addressing. Modules continue
to use TOC addressing.
- TOC address helpers and r2 are poisoned with -1 when running vmlinux.
r2 could be used for something useful once things are ironed out.
- Assembly must call C functions with @notoc annotation, or the linker
complains aobut a missing nop after the call. This is done with the
CFUNC macro introduced earlier.
- Boot: with the exception of prom_init, the execution branches to the
kernel virtual address early in boot, before any addresses are
generated, which ensures 34-bit pcrel addressing does not miss the
high PAGE_OFFSET bits. TOC relative addressing has a similar
requirement. prom_init does not go to the virtual address and its
addresses should not carry over to the post-prom kernel.
- Ftrace trampolines are converted from TOC addressing to pcrel
addressing, including module ftrace trampolines that currently use the
kernel TOC to find ftrace target functions.
- BPF function prologue and function calling generation are converted
from TOC to pcrel.
- copypage_64.S has an interesting problem, prefixed instructions have
alignment restrictions so the linker can add padding, which makes the
assembler treat the difference between two local labels as
non-constant even if alignment is arranged so padding is not required.
This may need toolchain help to solve nicely, for now move the prefix
instruction out of the alternate patch section to work around it.
This reduces kernel text size by about 6%.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-6-npiggin@gmail.com
This macro is to be used in assembly where C functions are called.
pcrel addressing mode requires branches to functions with a
localentry value of 1 to have either a trailing nop or @notoc.
This macro permits the latter without changing callers.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add dummy definitions to fix selftests build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-5-npiggin@gmail.com
Add an option to build kernel and module with prefixed instructions if
the CPU and toolchain support it.
This is not related to kernel support for userspace execution of
prefixed instructions.
Building with prefixed instructions breaks some extended inline asm
memory addressing, for example it will provide immediates that exceed
the range of simple load/store displacement. Whether this is a
toolchain or a kernel asm problem remains to be seen. For now, these
are replaced with simpler and less efficient direct register addressing
when compiling with prefixed.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-4-npiggin@gmail.com
This mostly consolidates the Book3E and Book3S behaviour in boot WRT
executing from the physical or virtual address.
Book3E sets up kernel virtual linear map in start_initialization_book3e
and runs from the virtual linear alias after that. This change makes
Book3S begin to execute from the virtual alias at the same point. Book3S
can not use its MMU for that at this point, but when the MMU is disabled,
the virtual linear address correctly aliases to physical memory because
the top bits of the address are ignored with MMU disabled.
Secondaries execute from the virtual address similarly early.
This reduces the differences between subarchs, but the main motivation
was to enable the PC-relative addressing ABI for Book3S, where pointer
calculations must execute from the virtual address or the top bits of
the pointer will be lost. This is similar to the requirement the TOC
relative addressing already has that the TOC pointer use its virtual
address.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-3-npiggin@gmail.com
A later change moves the non-prom case to run at the virtual address
earlier, which calls for virtual TOC and kernel base. Split these two
calculations for prom and non-prom to make that change simpler.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Retain relative_toc call for start_initialization_book3e]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-2-npiggin@gmail.com
When building with W=1 after commit 80b6093b55 ("kbuild: add -Wundef
to KBUILD_CPPFLAGS for W=1 builds"), the following warning occurs.
In file included from arch/powerpc/kvm/bookehv_interrupts.S:26:
arch/powerpc/kvm/../kernel/head_booke.h:20:6: warning: "THREAD_SHIFT" is not defined, evaluates to 0 [-Wundef]
20 | #if (THREAD_SHIFT < 15)
| ^~~~~~~~~~~~
THREAD_SHIFT is defined in thread_info.h but it is not directly included
in head_booke.h, so it is possible for THREAD_SHIFT to be undefined. Add
the include to ensure that THREAD_SHIFT is always defined.
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/202304050954.yskLdczH-lkp@intel.com/
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230406-wundef-thread_shift_booke-v1-1-8deffa4d84f9@kernel.org
syscalls do not set the PPR field in their interrupt frame and
return from syscall always sets the default PPR for userspace,
so setting the value in the ret_from_fork frame is not necessary
and mildly inconsistent. Remove it.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-9-npiggin@gmail.com
In the kernel user thread path, don't set _TIF_RESTOREALL because
the thread is required to call kernel_execve() before it returns,
which will set _TIF_RESTOREALL if necessary via start_thread().
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-8-npiggin@gmail.com
Kernel created user threads start similarly to kernel threads in that
they call a kernel function after first returning from _switch, so
they share ret_from_kernel_thread for this. Kernel threads never return
from that function though, whereas user threads often do (although some
don't, e.g., IO threads).
Split these startup functions in two, and catch kernel threads that
improperly return from their function. This is intended to make the
complicated code a little bit easier to understand.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-7-npiggin@gmail.com
When copy_thread is given a kernel function to run in arg->fn, this
does not necessarily mean it is a kernel thread. User threads can be
created this way (e.g., kernel_init, see also x86's copy_thread()).
These threads run a kernel function which may call kernel_execve()
and return, which returns like a userspace exec(2) syscall.
Kernel threads are to be differentiated with PF_KTHREAD, will always
have arg->fn set, and should never return from that function, instead
calling kthread_exit() to exit.
Create separate paths for the kthread and user kernel thread creation
logic. The kthread path will never exit and does not require a user
interrupt frame, so it gets a minimal stack frame.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-6-npiggin@gmail.com
If the system call return path always restores NVGPRs then there is no
need for ret_from_fork to do it. The HANDLER_RESTORE_NVGPRS does the
right thing for this.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-5-npiggin@gmail.com
The kernel thread path in copy_thread creates a user interrupt frame on
stack and stores the function and arg parameters there, and
ret_from_kernel_thread loads them. This is a slightly confusing way to
overload that frame. Non-volatile registers are loaded from the switch
frame, so the parameters can be stored there. The user interrupt frame
is now only used by user threads when they return to user.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-4-npiggin@gmail.com
The ret_from_fork code for 64e and 32-bit set r3 for
syscall_exit_prepare the same way that 64s does, so there should
be no need to special-case them in copy_thread.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-3-npiggin@gmail.com
The pkey registers (AMR, IAMR) do not get loaded from the switch frame
so it is pointless to save anything there. Remove the dead code.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230325122904.2375060-2-npiggin@gmail.com
Instead of open-coding it everywhere introduce a tiny helper that can be
used to iterate over each resource of a PCI device, and convert the most
obvious users into it.
While at it drop doubled empty line before pdev_sort_resources().
No functional changes intended.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230330162434.35055-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
"ranges" is a standard property with common parsing functions. Users
shouldn't be implementing their own parsing of it. Reimplement the
ISA brige "ranges" parsing using the common ranges iterator functions.
The common routines are flexible enough to work on PCI and non-PCI to
ISA bridges, so refactor pci_process_ISA_OF_ranges() and
isa_bridge_init_non_pci() into a single implementation.
Signed-off-by: Rob Herring <robh@kernel.org>
[mpe: Unsplit some strings and use pr_xxx()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230327223045.819852-1-robh@kernel.org
We need the fixes in here for testing, as well as the driver core
changes for documentation updates to build on.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Fix a false positive warning in __pte_needs_flush() (with DEBUG_VM=y).
- Fix oops when a PF_IO_WORKER thread tries to core dump.
- Don't try to reconfigure VAS when it's disabled.
Thanks to: Benjamin Gray, Haren Myneni, Jens Axboe, Nathan Lynch, Russell Currey.
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Merge tag 'powerpc-6.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Fix a false positive warning in __pte_needs_flush() (with DEBUG_VM=y)
- Fix oops when a PF_IO_WORKER thread tries to core dump
- Don't try to reconfigure VAS when it's disabled
Thanks to Benjamin Gray, Haren Myneni, Jens Axboe, Nathan Lynch, and
Russell Currey.
* tag 'powerpc-6.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/pseries/vas: Ignore VAS update for DLPAR if copy/paste is not enabled
powerpc: Don't try to copy PPR for task with NULL pt_regs
powerpc/64s: Fix __pte_needs_flush() false positive warning
It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties.
Convert reading boolean properties to of_property_read_bool().
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230310144659.1541127-1-robh@kernel.org
Nicholas Piggin
Uwe Kleine-König
Douglas Anderson
Nhat Pham
Christophe Leroy
Mark Rutland
Nathan Chancellor
Gaurav Batra
Jason Gunthorpe
ndesaulniers@google.com
Tejun Heo
Rob Herring
Linus Torvalds
Michael Ellerman
Josh Poimboeuf
Mika Westerberg
Greg Kroah-Hartman