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Author SHA1 Message Date
Aneesh Kumar K.V
ec4abf1e70 powerpc/mm/hash64: use _PAGE_PTE when checking for pte_present
This makes the pte_present check stricter by checking for additional _PAGE_PTE
bit. A level 1 pte pointer (THP pte) can be switched to a pointer to level 0 pte
page table page by following two operations.

1) THP split.
2) madvise(MADV_DONTNEED) in parallel to page fault.

A lockless page table walk need to make sure we can handle such changes
gracefully.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-4-aneesh.kumar@linux.ibm.com
2020-05-05 21:20:14 +10:00
Aneesh Kumar K.V
fe4a6856cb powerpc/pkeys: Avoid using lockless page table walk
Fetch pkey from vma instead of linux page table. Also document the fact that in
some cases the pkey returned in siginfo won't be the same as the one we took
keyfault on. Even with linux page table walk, we can end up in a similar scenario.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200505071729.54912-2-aneesh.kumar@linux.ibm.com
2020-05-05 21:20:13 +10:00
Hari Bathini
02c04e374e powerpc/fadump: use static allocation for reserved memory ranges
At times, memory ranges have to be looked up during early boot, when
kernel couldn't be initialized for dynamic memory allocation. In fact,
reserved-ranges look up is needed during FADump memory reservation.
Without accounting for reserved-ranges in reserving memory for FADump,
MPIPL boot fails with memory corruption issues. So, extend memory
ranges handling to support static allocation and populate reserved
memory ranges during early boot.

Fixes: dda9dbfeeb ("powerpc/fadump: consider reserved ranges while releasing memory")
Cc: stable@vger.kernel.org
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/158737294432.26700.4830263187856221314.stgit@hbathini.in.ibm.com
2020-05-04 22:29:58 +10:00
Michael Ellerman
0094368e3b powerpc/64s: Fix unrecoverable SLB crashes due to preemption check
Hugh reported that his trusty G5 crashed after a few hours under load
with an "Unrecoverable exception 380".

The crash is in interrupt_return() where we check lazy_irq_pending(),
which calls get_paca() and with CONFIG_DEBUG_PREEMPT=y that goes to
check_preemption_disabled() via debug_smp_processor_id().

As Nick explained on the list:

  Problem is MSR[RI] is cleared here, ready to do the last few things
  for interrupt return where we're not allowed to take any other
  interrupts.

  SLB interrupts can happen just about anywhere aside from kernel
  text, global variables, and stack. When that hits, it appears to be
  unrecoverable due to RI=0.

The problematic access is in preempt_count() which is:

	return READ_ONCE(current_thread_info()->preempt_count);

Because of THREAD_INFO_IN_TASK, current_thread_info() just points to
current, so the access is to somewhere in kernel memory, but not on
the stack or in .data, which means it can cause an SLB miss. If we
take an SLB miss with RI=0 it is fatal.

The easiest solution is to add a version of lazy_irq_pending() that
doesn't do the preemption check and call it from the interrupt return
path.

Fixes: 68b34588e2 ("powerpc/64/sycall: Implement syscall entry/exit logic in C")
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200502143316.929341-1-mpe@ellerman.id.au
2020-05-04 09:18:06 +10:00
Christophe Leroy
4fe5cda9f8 powerpc/uaccess: Implement user_read_access_begin and user_write_access_begin
Add support for selective read or write user access with
user_read_access_begin/end and user_write_access_begin/end.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6c83af0f0809ef2a955c39ac622767f6cbede035.1585898438.git.christophe.leroy@c-s.fr
2020-05-01 12:37:15 +10:00
Christophe Leroy
17bc43367f powerpc/uaccess: Implement unsafe_copy_to_user() as a simple loop
At the time being, unsafe_copy_to_user() is based on
raw_copy_to_user() which calls __copy_tofrom_user().

__copy_tofrom_user() is a big optimised function to copy big amount
of data. It aligns destinations to cache line in order to use
dcbz instruction.

Today unsafe_copy_to_user() is called only from filldir().
It is used to mainly copy small amount of data like filenames,
so __copy_tofrom_user() is not fit.

Also, unsafe_copy_to_user() is used within user_access_begin/end
sections. In those section, it is preferable to not call functions.

Rewrite unsafe_copy_to_user() as a macro that uses __put_user_goto().
We first perform a loop of long, then we finish with necessary
complements.

unsafe_copy_to_user() might be used in the near future to copy
fixed-size data, like pt_regs structs during signal processing.
Having it as a macro allows GCC to optimise it for instead when
it knows the size in advance, it can unloop loops, drop complements
when the size is a multiple of longs, etc ...

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fe952112c29bf6a0a2778c9e6bbb4f4afd2c4258.1587143308.git.christophe.leroy@c-s.fr
2020-04-30 20:30:40 +10:00
Christophe Leroy
334710b149 powerpc/uaccess: Implement unsafe_put_user() using 'asm goto'
unsafe_put_user() is designed to take benefit of 'asm goto'.

Instead of using the standard __put_user() approach and branch
based on the returned error, use 'asm goto' and make the
exception code branch directly to the error label. There is
no code anymore in the fixup section.

This change significantly simplifies functions using
unsafe_put_user()

Small exemple of the benefit with the following code:

struct test {
	u32 item1;
	u16 item2;
	u8 item3;
	u64 item4;
};

int set_test_to_user(struct test __user *test, u32 item1, u16 item2, u8 item3, u64 item4)
{
	unsafe_put_user(item1, &test->item1, failed);
	unsafe_put_user(item2, &test->item2, failed);
	unsafe_put_user(item3, &test->item3, failed);
	unsafe_put_user(item4, &test->item4, failed);
	return 0;
failed:
	return -EFAULT;
}

Before the patch:

00000be8 <set_test_to_user>:
 be8:	39 20 00 00 	li      r9,0
 bec:	90 83 00 00 	stw     r4,0(r3)
 bf0:	2f 89 00 00 	cmpwi   cr7,r9,0
 bf4:	40 9e 00 38 	bne     cr7,c2c <set_test_to_user+0x44>
 bf8:	b0 a3 00 04 	sth     r5,4(r3)
 bfc:	2f 89 00 00 	cmpwi   cr7,r9,0
 c00:	40 9e 00 2c 	bne     cr7,c2c <set_test_to_user+0x44>
 c04:	98 c3 00 06 	stb     r6,6(r3)
 c08:	2f 89 00 00 	cmpwi   cr7,r9,0
 c0c:	40 9e 00 20 	bne     cr7,c2c <set_test_to_user+0x44>
 c10:	90 e3 00 08 	stw     r7,8(r3)
 c14:	91 03 00 0c 	stw     r8,12(r3)
 c18:	21 29 00 00 	subfic  r9,r9,0
 c1c:	7d 29 49 10 	subfe   r9,r9,r9
 c20:	38 60 ff f2 	li      r3,-14
 c24:	7d 23 18 38 	and     r3,r9,r3
 c28:	4e 80 00 20 	blr
 c2c:	38 60 ff f2 	li      r3,-14
 c30:	4e 80 00 20 	blr

00000000 <.fixup>:
	...
  b8:	39 20 ff f2 	li      r9,-14
  bc:	48 00 00 00 	b       bc <.fixup+0xbc>
			bc: R_PPC_REL24	.text+0xbf0
  c0:	39 20 ff f2 	li      r9,-14
  c4:	48 00 00 00 	b       c4 <.fixup+0xc4>
			c4: R_PPC_REL24	.text+0xbfc
  c8:	39 20 ff f2 	li      r9,-14
  cc:	48 00 00 00 	b       cc <.fixup+0xcc>
  d0:	39 20 ff f2 	li      r9,-14
  d4:	48 00 00 00 	b       d4 <.fixup+0xd4>
			d4: R_PPC_REL24	.text+0xc18

00000000 <__ex_table>:
	...
			a0: R_PPC_REL32	.text+0xbec
			a4: R_PPC_REL32	.fixup+0xb8
			a8: R_PPC_REL32	.text+0xbf8
			ac: R_PPC_REL32	.fixup+0xc0
			b0: R_PPC_REL32	.text+0xc04
			b4: R_PPC_REL32	.fixup+0xc8
			b8: R_PPC_REL32	.text+0xc10
			bc: R_PPC_REL32	.fixup+0xd0
			c0: R_PPC_REL32	.text+0xc14
			c4: R_PPC_REL32	.fixup+0xd0

After the patch:

00000be8 <set_test_to_user>:
 be8:	90 83 00 00 	stw     r4,0(r3)
 bec:	b0 a3 00 04 	sth     r5,4(r3)
 bf0:	98 c3 00 06 	stb     r6,6(r3)
 bf4:	90 e3 00 08 	stw     r7,8(r3)
 bf8:	91 03 00 0c 	stw     r8,12(r3)
 bfc:	38 60 00 00 	li      r3,0
 c00:	4e 80 00 20 	blr
 c04:	38 60 ff f2 	li      r3,-14
 c08:	4e 80 00 20 	blr

00000000 <__ex_table>:
	...
			a0: R_PPC_REL32	.text+0xbe8
			a4: R_PPC_REL32	.text+0xc04
			a8: R_PPC_REL32	.text+0xbec
			ac: R_PPC_REL32	.text+0xc04
			b0: R_PPC_REL32	.text+0xbf0
			b4: R_PPC_REL32	.text+0xc04
			b8: R_PPC_REL32	.text+0xbf4
			bc: R_PPC_REL32	.text+0xc04
			c0: R_PPC_REL32	.text+0xbf8
			c4: R_PPC_REL32	.text+0xc04

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/23e680624680a9a5405f4b88740d2596d4b17c26.1587143308.git.christophe.leroy@c-s.fr
2020-04-30 20:30:40 +10:00
Nicholas Piggin
d02f6b7dab powerpc/uaccess: Evaluate macro arguments once, before user access is allowed
get/put_user() can be called with nontrivial arguments. fs/proc/page.c
has a good example:

    if (put_user(stable_page_flags(ppage), out)) {

stable_page_flags() is quite a lot of code, including spin locks in
the page allocator.

Ensure these arguments are evaluated before user access is allowed.

This improves security by reducing code with access to userspace, but
it also fixes a PREEMPT bug with KUAP on powerpc/64s:
stable_page_flags() is currently called with AMR set to allow writes,
it ends up calling spin_unlock(), which can call preempt_schedule. But
the task switch code can not be called with AMR set (it relies on
interrupts saving the register), so this blows up.

It's fine if the code inside allow_user_access() is preemptible,
because a timer or IPI will save the AMR, but it's not okay to
explicitly cause a reschedule.

Fixes: de78a9c42a ("powerpc: Add a framework for Kernel Userspace Access Protection")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200407041245.600651-1-npiggin@gmail.com
2020-04-30 20:21:44 +10:00
Gautham R. Shenoy
6909f179ca powerpc/sysfs: Show idle_purr and idle_spurr for every CPU
On Pseries LPARs, to calculate utilization, we need to know the
[S]PURR ticks when the CPUs were busy or idle.

The total PURR and SPURR ticks are already exposed via the per-cpu
sysfs files "purr" and "spurr". This patch adds support for exposing
the idle PURR and SPURR ticks via new per-cpu sysfs files named
"idle_purr" and "idle_spurr".

This patch also adds helper functions to accurately read the values of
idle_purr and idle_spurr especially from an interrupt context between
when the interrupt has occurred between the pseries_idle_prolog() and
pseries_idle_epilog(). This will ensure that the idle purr/spurr
values corresponding to the latest idle period is accounted for before
these values are read.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1586249263-14048-5-git-send-email-ego@linux.vnet.ibm.com
2020-04-30 12:35:26 +10:00
Gautham R. Shenoy
dc8afce5f4 powerpc/pseries: Account for SPURR ticks on idle CPUs
On Pseries LPARs, to calculate utilization, we need to know the
[S]PURR ticks when the CPUs were busy or idle.

Via pseries_idle_prolog(), pseries_idle_epilog(), we track the idle
PURR ticks in the VPA variable "wait_state_cycles". This patch extends
the support to account for the idle SPURR ticks.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1586249263-14048-4-git-send-email-ego@linux.vnet.ibm.com
2020-04-30 12:35:26 +10:00
Gautham R. Shenoy
c4019198cf powerpc/idle: Store PURR snapshot in a per-cpu global variable
Currently when CPU goes idle, we take a snapshot of PURR via
pseries_idle_prolog() which is used at the CPU idle exit to compute
the idle PURR cycles via the function pseries_idle_epilog().  Thus,
the value of idle PURR cycle thus read before pseries_idle_prolog() and
after pseries_idle_epilog() is always correct.

However, if we were to read the idle PURR cycles from an interrupt
context between pseries_idle_prolog() and pseries_idle_epilog() (this
will be done in a future patch), then, the value of the idle PURR thus
read will not include the cycles spent in the most recent idle period.
Thus, in that interrupt context, we will need access to the snapshot
of the PURR before going idle, in order to compute the idle PURR
cycles for the latest idle duration.

In this patch, we save the snapshot of PURR in pseries_idle_prolog()
in a per-cpu variable, instead of on the stack, so that it can be
accessed from an interrupt context.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1586249263-14048-3-git-send-email-ego@linux.vnet.ibm.com
2020-04-30 12:35:26 +10:00
Gautham R. Shenoy
e4a884cc28 powerpc: Move idle_loop_prolog()/epilog() functions to header file
Currently prior to entering an idle state on a Linux Guest, the
pseries cpuidle driver implement an idle_loop_prolog() and
idle_loop_epilog() functions which ensure that idle_purr is correctly
computed, and the hypervisor is informed that the CPU cycles have been
donated.

These prolog and epilog functions are also required in the default
idle call, i.e pseries_lpar_idle(). Hence move these accessor
functions to a common header file and call them from
pseries_lpar_idle(). Since the existing header files such as
asm/processor.h have enough clutter, create a new header file
asm/idle.h. Finally rename idle_loop_prolog() and idle_loop_epilog()
to pseries_idle_prolog() and pseries_idle_epilog() as they are only
relavent for on pseries guests.

Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1586249263-14048-2-git-send-email-ego@linux.vnet.ibm.com
2020-04-30 12:35:26 +10:00
Masahiro Yamada
62d0fd591d arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h>
As the bug report [1] pointed out, <linux/vermagic.h> must be included
after <linux/module.h>.

I believe we should not impose any include order restriction. We often
sort include directives alphabetically, but it is just coding style
convention. Technically, we can include header files in any order by
making every header self-contained.

Currently, arch-specific MODULE_ARCH_VERMAGIC is defined in
<asm/module.h>, which is not included from <linux/vermagic.h>.

Hence, the straight-forward fix-up would be as follows:

|--- a/include/linux/vermagic.h
|+++ b/include/linux/vermagic.h
|@@ -1,5 +1,6 @@
| /* SPDX-License-Identifier: GPL-2.0 */
| #include <generated/utsrelease.h>
|+#include <linux/module.h>
|
| /* Simply sanity version stamp for modules. */
| #ifdef CONFIG_SMP

This works enough, but for further cleanups, I split MODULE_ARCH_VERMAGIC
definitions into <asm/vermagic.h>.

With this, <linux/module.h> and <linux/vermagic.h> will be orthogonal,
and the location of MODULE_ARCH_VERMAGIC definitions will be consistent.

For arc and ia64, MODULE_PROC_FAMILY is only used for defining
MODULE_ARCH_VERMAGIC. I squashed it.

For hexagon, nds32, and xtensa, I removed <asm/modules.h> entirely
because they contained nothing but MODULE_ARCH_VERMAGIC definition.
Kbuild will automatically generate <asm/modules.h> at build-time,
wrapping <asm-generic/module.h>.

[1] https://lore.kernel.org/lkml/20200411155623.GA22175@zn.tnic

Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
2020-04-23 10:50:26 +09:00
Stephen Rothwell
45591da765 powerpc/vas: Include linux/types.h in uapi/asm/vas-api.h
allyesconfig fails with:
  ./usr/include/asm/vas-api.h:15:2: error: unknown type name '__u32'
     15 |  __u32 version;
        |  ^~~~~
  ./usr/include/asm/vas-api.h:16:2: error: unknown type name '__s16'
     16 |  __s16 vas_id; /* specific instance of vas or -1 for default */
        |  ^~~~~
  ./usr/include/asm/vas-api.h:17:2: error: unknown type name '__u16'
     17 |  __u16 reserved1;
        |  ^~~~~
  ./usr/include/asm/vas-api.h:18:2: error: unknown type name '__u64'
     18 |  __u64 flags; /* Future use */
        |  ^~~~~
  ./usr/include/asm/vas-api.h:19:2: error: unknown type name '__u64'
     19 |  __u64 reserved2[6];
        |  ^~~~~

uapi headers should be self contained, so add an include of
linux/types.h.

Fixes: 45f25a79fe ("powerpc/vas: Define VAS_TX_WIN_OPEN ioctl API")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Haren Myneni <haren@linux.ibm.com>
[mpe: Flesh out change log from linux-next error report]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200422154129.11f988fd@canb.auug.org.au
2020-04-22 20:02:14 +10:00
Mauro Carvalho Chehab
72ef5e52b3 docs: fix broken references to text files
Several references got broken due to txt to ReST conversion.

Several of them can be automatically fixed with:

	scripts/documentation-file-ref-check --fix

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> # hwtracing/coresight/Kconfig
Reviewed-by: Paul E. McKenney <paulmck@kernel.org> # memory-barrier.txt
Acked-by: Alex Shi <alex.shi@linux.alibaba.com> # translations/zh_CN
Acked-by: Federico Vaga <federico.vaga@vaga.pv.it> # translations/it_IT
Acked-by: Marc Zyngier <maz@kernel.org> # kvm/arm64
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6f919ddb83a33b5f2a63b6b5f0575737bb2b36aa.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:35:59 -06:00
Haren Myneni
040b00acec crypto/nx: Remove 'pid' in vas_tx_win_attr struct
When window is opened, pid reference is taken for user space
windows. Not needed for kernel windows. So remove 'pid' in
vas_tx_win_attr struct.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587114674.2275.1132.camel@hbabu-laptop
2020-04-20 16:53:14 +10:00
Haren Myneni
dda44eb29c powerpc/vas: Add VAS user space API
On power9, userspace can send GZIP compression requests directly to NX
once kernel establishes NX channel / window with VAS. This patch provides
user space API which allows user space to establish channel using open
VAS_TX_WIN_OPEN ioctl, mmap and close operations.

Each window corresponds to file descriptor and application can open
multiple windows. After the window is opened, VAS_TX_WIN_OPEN icoctl to
open a window on specific VAS instance, mmap() system call to map
the hardware address of engine's request queue into the application's
virtual address space.

Then the application can then submit one or more requests to the the
engine by using the copy/paste instructions and pasting the CRBs to
the virtual address (aka paste_address) returned by mmap().

Only NX GZIP coprocessor type is supported right now and allow GZIP
engine access via /dev/crypto/nx-gzip device node.

Thanks to Michael Ellerman for his changes and suggestions to make the
ioctl generic to support any coprocessor type.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587114121.2275.1109.camel@hbabu-laptop
2020-04-20 16:53:14 +10:00
Haren Myneni
45f25a79fe powerpc/vas: Define VAS_TX_WIN_OPEN ioctl API
Define the VAS_TX_WIN_OPEN ioctl interface for NX GZIP access
from user space. This interface is used to open GZIP send window and
mmap region which can be used by userspace to send requests to NX
directly with copy/paste instructions.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587114065.2275.1106.camel@hbabu-laptop
2020-04-20 16:53:13 +10:00
Haren Myneni
c420644c0a powerpc: Use mm_context vas_windows counter to issue CP_ABORT
set_thread_uses_vas() sets used_vas flag for a process that opened VAS
window and issue CP_ABORT during context switch for only that process.
In multi-thread application, windows can be shared. For example Thread
A can open a window and Thread B can run COPY/PASTE instructions to
send NX request which may cause corruption or snooping or a covert
channel Also once this flag is set, continue to run CP_ABORT even the
VAS window is closed.

So define vas-windows counter in process mm_context, increment this
counter for each window open and decrement it for window close. If
vas-windows is set, issue CP_ABORT during context switch. It means
clear the foreign real address mapping only if the process / thread
uses COPY/PASTE. Then disable it for that process if windows are not
open.

Moved set_thread_uses_vas() code to vas_tx_win_open() as this
functionality is needed only for userspace open windows. We are adding
VAS userspace support along with this fix. So no need to include this
fix in stable releases.

Fixes: 9d2a4d7133 ("powerpc: Define set_thread_uses_vas()")
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Reported-by: Nicholas Piggin <npiggin@gmail.com>
Suggested-by: Milton Miller <miltonm@us.ibm.com>
Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587017291.2275.1077.camel@hbabu-laptop
2020-04-20 16:53:01 +10:00
Haren Myneni
73a8077938 powerpc/vas: Define nx_fault_stamp in coprocessor_request_block
Kernel sets fault address and status in CRB for NX page fault on user
space address after processing page fault. User space gets the signal
and handles the fault mentioned in CRB by bringing the page in to
memory and send NX request again.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587016769.2275.1048.camel@hbabu-laptop
2020-04-20 16:53:00 +10:00
Haren Myneni
8d0ea29db5 powerpc/xive: Define xive_native_alloc_irq_on_chip()
This function allocates IRQ on a specific chip. VAS needs per chip
IRQ allocation and will have IRQ handler per VAS instance.

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587016720.2275.1047.camel@hbabu-laptop
2020-04-20 16:52:59 +10:00
Logan Gunthorpe
4e00c5affd powerpc/mm: thread pgprot_t through create_section_mapping()
In prepartion to support a pgprot_t argument for arch_add_memory().

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric Badger <ebadger@gigaio.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200306170846.9333-6-logang@deltatee.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Anshuman Khandual
c62da0c35d mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS
This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the
existing VM_STACK_DEFAULT_FLAGS.  While here, also define some more
macros with standard VMA access flag combinations that are used
frequently across many platforms.  Apart from simplification, this
reduces code duplication as well.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Linus Torvalds
e4da01d833 powerpc updates for 5.7 #2
- A fix for a crash in machine check handling on pseries (ie. guests)
 
  - A small series to make it possible to disable CONFIG_COMPAT, and turn it off
    by default for ppc64le where it's not used.
 
  - A few other miscellaneous fixes and small improvements.
 
 Thanks to:
   Alexey Kardashevskiy, Anju T Sudhakar, Arnd Bergmann, Christophe Leroy, Dan
   Carpenter, Ganesh Goudar, Geert Uytterhoeven, Geoff Levand, Mahesh Salgaonkar,
   Markus Elfring, Michal Suchanek, Nicholas Piggin, Stephen Boyd, Wen Xiong.
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Merge tag 'powerpc-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull more powerpc updates from Michael Ellerman:
 "The bulk of this is the series to make CONFIG_COMPAT user-selectable,
  it's been around for a long time but was blocked behind the
  syscall-in-C series.

  Plus there's also a few fixes and other minor things.

  Summary:

   - A fix for a crash in machine check handling on pseries (ie. guests)

   - A small series to make it possible to disable CONFIG_COMPAT, and
     turn it off by default for ppc64le where it's not used.

   - A few other miscellaneous fixes and small improvements.

  Thanks to: Alexey Kardashevskiy, Anju T Sudhakar, Arnd Bergmann,
  Christophe Leroy, Dan Carpenter, Ganesh Goudar, Geert Uytterhoeven,
  Geoff Levand, Mahesh Salgaonkar, Markus Elfring, Michal Suchanek,
  Nicholas Piggin, Stephen Boyd, Wen Xiong"

* tag 'powerpc-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  selftests/powerpc: Always build the tm-poison test 64-bit
  powerpc: Improve ppc_save_regs()
  Revert "powerpc/64: irq_work avoid interrupt when called with hardware irqs enabled"
  powerpc/time: Replace <linux/clk-provider.h> by <linux/of_clk.h>
  powerpc/pseries/ddw: Extend upper limit for huge DMA window for persistent memory
  powerpc/perf: split callchain.c by bitness
  powerpc/64: Make COMPAT user-selectable disabled on littleendian by default.
  powerpc/64: make buildable without CONFIG_COMPAT
  powerpc/perf: consolidate valid_user_sp -> invalid_user_sp
  powerpc/perf: consolidate read_user_stack_32
  powerpc: move common register copy functions from signal_32.c to signal.c
  powerpc: Add back __ARCH_WANT_SYS_LLSEEK macro
  powerpc/ps3: Set CONFIG_UEVENT_HELPER=y in ps3_defconfig
  powerpc/ps3: Remove an unneeded NULL check
  powerpc/ps3: Remove duplicate error message
  powerpc/powernv: Re-enable imc trace-mode in kernel
  powerpc/perf: Implement a global lock to avoid races between trace, core and thread imc events.
  powerpc/pseries: Fix MCE handling on pseries
  selftests/eeh: Skip ahci adapters
  powerpc/64s: Fix doorbell wakeup msgclr optimisation
2020-04-09 11:01:42 -07:00
Linus Torvalds
d38c07afc3 powerpc updates for 5.7
- A large series from Nick for 64-bit to further rework our exception vectors,
    and rewrite portions of the syscall entry/exit and interrupt return in C. The
    result is much easier to follow code that is also faster in general.
 
  - Cleanup of our ptrace code to split various parts out that had become badly
    intertwined with #ifdefs over the years.
 
  - Changes to our NUMA setup under the PowerVM hypervisor which should
    hopefully avoid non-sensical topologies which can lead to warnings from the
    workqueue code and other problems.
 
  - MAINTAINERS updates to remove some of our old orphan entries and update the
    status of others.
 
  - Quite a few other small changes and fixes all over the map.
 
 Thanks to:
   Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh
   Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET,
   Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David
   Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R.
   Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie
   Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger,
   Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh
   Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira,
   Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
   Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers,
   Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi
   Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek,
   Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen
   Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing.
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Merge tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Slightly late as I had to rebase mid-week to insert a bug fix:

   - A large series from Nick for 64-bit to further rework our exception
     vectors, and rewrite portions of the syscall entry/exit and
     interrupt return in C. The result is much easier to follow code
     that is also faster in general.

   - Cleanup of our ptrace code to split various parts out that had
     become badly intertwined with #ifdefs over the years.

   - Changes to our NUMA setup under the PowerVM hypervisor which should
     hopefully avoid non-sensical topologies which can lead to warnings
     from the workqueue code and other problems.

   - MAINTAINERS updates to remove some of our old orphan entries and
     update the status of others.

   - Quite a few other small changes and fixes all over the map.

  Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew
  Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen
  Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement
  Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas,
  Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman,
  Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara,
  Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor,
  Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar,
  Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael
  Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick
  Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat,
  Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff,
  Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G
  Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel
  Datwyler, Vaibhav Jain, YueHaibing"

* tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
  powerpc: Make setjmp/longjmp signature standard
  powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type
  powerpc: Suppress .eh_frame generation
  powerpc: Drop -fno-dwarf2-cfi-asm
  powerpc/32: drop unused ISA_DMA_THRESHOLD
  powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces
  selftests/powerpc: Fix try-run when source tree is not writable
  powerpc/vmlinux.lds: Explicitly retain .gnu.hash
  powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c
  powerpc/ptrace: create ppc_gethwdinfo()
  powerpc/ptrace: create ptrace_get_debugreg()
  powerpc/ptrace: split out ADV_DEBUG_REGS related functions.
  powerpc/ptrace: move register viewing functions out of ptrace.c
  powerpc/ptrace: split out TRANSACTIONAL_MEM related functions.
  powerpc/ptrace: split out SPE related functions.
  powerpc/ptrace: split out ALTIVEC related functions.
  powerpc/ptrace: split out VSX related functions.
  powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET
  powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64
  powerpc/ptrace: remove unused header includes
  ...
2020-04-05 11:12:59 -07:00
Linus Torvalds
8c1b724ddb ARM:
* GICv4.1 support
 * 32bit host removal
 
 PPC:
 * secure (encrypted) using under the Protected Execution Framework
 ultravisor
 
 s390:
 * allow disabling GISA (hardware interrupt injection) and protected
 VMs/ultravisor support.
 
 x86:
 * New dirty bitmap flag that sets all bits in the bitmap when dirty
 page logging is enabled; this is faster because it doesn't require bulk
 modification of the page tables.
 * Initial work on making nested SVM event injection more similar to VMX,
 and less buggy.
 * Various cleanups to MMU code (though the big ones and related
 optimizations were delayed to 5.8).  Instead of using cr3 in function
 names which occasionally means eptp, KVM too has standardized on "pgd".
 * A large refactoring of CPUID features, which now use an array that
 parallels the core x86_features.
 * Some removal of pointer chasing from kvm_x86_ops, which will also be
 switched to static calls as soon as they are available.
 * New Tigerlake CPUID features.
 * More bugfixes, optimizations and cleanups.
 
 Generic:
 * selftests: cleanups, new MMU notifier stress test, steal-time test
 * CSV output for kvm_stat.
 
 KVM/MIPS has been broken since 5.5, it does not compile due to a patch committed
 by MIPS maintainers.  I had already prepared a fix, but the MIPS maintainers
 prefer to fix it in generic code rather than KVM so they are taking care of it.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - GICv4.1 support

   - 32bit host removal

  PPC:
   - secure (encrypted) using under the Protected Execution Framework
     ultravisor

  s390:
   - allow disabling GISA (hardware interrupt injection) and protected
     VMs/ultravisor support.

  x86:
   - New dirty bitmap flag that sets all bits in the bitmap when dirty
     page logging is enabled; this is faster because it doesn't require
     bulk modification of the page tables.

   - Initial work on making nested SVM event injection more similar to
     VMX, and less buggy.

   - Various cleanups to MMU code (though the big ones and related
     optimizations were delayed to 5.8). Instead of using cr3 in
     function names which occasionally means eptp, KVM too has
     standardized on "pgd".

   - A large refactoring of CPUID features, which now use an array that
     parallels the core x86_features.

   - Some removal of pointer chasing from kvm_x86_ops, which will also
     be switched to static calls as soon as they are available.

   - New Tigerlake CPUID features.

   - More bugfixes, optimizations and cleanups.

  Generic:
   - selftests: cleanups, new MMU notifier stress test, steal-time test

   - CSV output for kvm_stat"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (277 commits)
  x86/kvm: fix a missing-prototypes "vmread_error"
  KVM: x86: Fix BUILD_BUG() in __cpuid_entry_get_reg() w/ CONFIG_UBSAN=y
  KVM: VMX: Add a trampoline to fix VMREAD error handling
  KVM: SVM: Annotate svm_x86_ops as __initdata
  KVM: VMX: Annotate vmx_x86_ops as __initdata
  KVM: x86: Drop __exit from kvm_x86_ops' hardware_unsetup()
  KVM: x86: Copy kvm_x86_ops by value to eliminate layer of indirection
  KVM: x86: Set kvm_x86_ops only after ->hardware_setup() completes
  KVM: VMX: Configure runtime hooks using vmx_x86_ops
  KVM: VMX: Move hardware_setup() definition below vmx_x86_ops
  KVM: x86: Move init-only kvm_x86_ops to separate struct
  KVM: Pass kvm_init()'s opaque param to additional arch funcs
  s390/gmap: return proper error code on ksm unsharing
  KVM: selftests: Fix cosmetic copy-paste error in vm_mem_region_move()
  KVM: Fix out of range accesses to memslots
  KVM: X86: Micro-optimize IPI fastpath delay
  KVM: X86: Delay read msr data iff writes ICR MSR
  KVM: PPC: Book3S HV: Add a capability for enabling secure guests
  KVM: arm64: GICv4.1: Expose HW-based SGIs in debugfs
  KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs
  ...
2020-04-02 15:13:15 -07:00
Masahiro Yamada
630f289b71 asm-generic: make more kernel-space headers mandatory
Change a header to mandatory-y if both of the following are met:

[1] At least one architecture (except um) specifies it as generic-y in
    arch/*/include/asm/Kbuild

[2] Every architecture (except um) either has its own implementation
    (arch/*/include/asm/*.h) or specifies it as generic-y in
    arch/*/include/asm/Kbuild

This commit was generated by the following shell script.

----------------------------------->8-----------------------------------

arches=$(cd arch; ls -1 | sed -e '/Kconfig/d' -e '/um/d')

tmpfile=$(mktemp)

grep "^mandatory-y +=" include/asm-generic/Kbuild > $tmpfile

find arch -path 'arch/*/include/asm/Kbuild' |
	xargs sed -n 's/^generic-y += \(.*\)/\1/p' | sort -u |
while read header
do
	mandatory=yes

	for arch in $arches
	do
		if ! grep -q "generic-y += $header" arch/$arch/include/asm/Kbuild &&
			! [ -f arch/$arch/include/asm/$header ]; then
			mandatory=no
			break
		fi
	done

	if [ "$mandatory" = yes ]; then
		echo "mandatory-y += $header" >> $tmpfile

		for arch in $arches
		do
			sed -i "/generic-y += $header/d" arch/$arch/include/asm/Kbuild
		done
	fi

done

sed -i '/^mandatory-y +=/d' include/asm-generic/Kbuild

LANG=C sort $tmpfile >> include/asm-generic/Kbuild

----------------------------------->8-----------------------------------

One obvious benefit is the diff stat:

 25 files changed, 52 insertions(+), 557 deletions(-)

It is tedious to list generic-y for each arch that needs it.

So, mandatory-y works like a fallback default (by just wrapping
asm-generic one) when arch does not have a specific header
implementation.

See the following commits:

def3f7cefe
a1b39bae16

It is tedious to convert headers one by one, so I processed by a shell
script.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/20200210175452.5030-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Michal Suchanek
0a7601b6ff powerpc/64: make buildable without CONFIG_COMPAT
There are numerous references to 32bit functions in generic and 64bit
code so ifdef them out.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e5619617020ef3a1f54f0c076e7d74cb9ec9f3bf.1584699455.git.msuchanek@suse.de
2020-04-03 00:10:00 +11:00
Michal Suchanek
9e62ccec3b powerpc: Add back __ARCH_WANT_SYS_LLSEEK macro
This partially reverts commit caf6f9c8a3 ("asm-generic: Remove
unneeded __ARCH_WANT_SYS_LLSEEK macro")

When CONFIG_COMPAT is disabled on ppc64 the kernel does not build.

There is resistance to both removing the llseek syscall from the 64bit
syscall tables and building the llseek interface unconditionally.


Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/lkml/20190828151552.GA16855@infradead.org/
Link: https://lore.kernel.org/lkml/20190829214319.498c7de2@naga/
Link: https://lore.kernel.org/r/dd4575c51e31766e87f7e7fa121d099ab78d3290.1584699455.git.msuchanek@suse.de
2020-04-03 00:09:59 +11:00
Clement Courbet
c17eb4dca5 powerpc: Make setjmp/longjmp signature standard
Declaring setjmp()/longjmp() as taking longs makes the signature
non-standard, and makes clang complain. In the past, this has been
worked around by adding -ffreestanding to the compile flags.

The implementation looks like it only ever propagates the value
(in longjmp) or sets it to 1 (in setjmp), and we only call longjmp
with integer parameters.

This allows removing -ffreestanding from the compilation flags.

Fixes: c9029ef9c9 ("powerpc: Avoid clang warnings around setjmp and longjmp")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Clement Courbet <courbet@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200330080400.124803-1-courbet@google.com
2020-04-01 14:30:51 +11:00
Mike Rapoport
b77afad84e powerpc/32: drop unused ISA_DMA_THRESHOLD
The ISA_DMA_THRESHOLD variable is set by several platforms but never
referenced.
Remove it.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191125092033.20014-1-rppt@kernel.org
2020-04-01 14:30:50 +11:00
Christophe Leroy
f1763e623c powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64
Drop a bunch of #ifdefs CONFIG_PPC64 that are not vital.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/af38b87a7e1e3efe4f9b664eaeb029e6e7d69fdb.1582848567.git.christophe.leroy@c-s.fr
2020-04-01 14:30:47 +11:00
Nicholas Piggin
6cc0c16d82 powerpc/64s: Implement interrupt exit logic in C
Implement the bulk of interrupt return logic in C. The asm return code
must handle a few cases: restoring full GPRs, and emulating stack
store.

The stack store emulation is significantly simplfied, rather than
creating a new return frame and switching to that before performing
the store, it uses the PACA to keep a scratch register around to
perform the store.

The asm return code is moved into 64e for now. The new logic has made
allowance for 64e, but I don't have a full environment that works well
to test it, and even booting in emulated qemu is not great for stress
testing. 64e shouldn't be too far off working with this, given a bit
more testing and auditing of the logic.

This is slightly faster on a POWER9 (page fault speed increases about
1.1%), probably due to reduced mtmsrd.

mpe: Includes fixes from Nick for _TIF_EMULATE_STACK_STORE
handling (including the fast_interrupt_return path), to remove
trace_hardirqs_on(), and fixes the interrupt-return part of the
MSR_VSX restore bug caught by tm-unavailable selftest.

mpe: Incorporate fix from Nick:

The return-to-kernel path has to replay any soft-pending interrupts if
it is returning to a context that had interrupts soft-enabled. It has
to do this carefully and avoid plain enabling interrupts if this is an
irq context, which can cause multiple nesting of interrupts on the
stack, and other unexpected issues.

The code which avoided this case got the soft-mask state wrong, and
marked interrupts as enabled before going around again to retry. This
seems to be mostly harmless except when PREEMPT=y, this calls
preempt_schedule_irq with irqs apparently enabled and runs into a BUG
in kernel/sched/core.c

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-29-npiggin@gmail.com
2020-04-01 13:42:14 +11:00
Nicholas Piggin
3282a3da25 powerpc/64: Implement soft interrupt replay in C
When local_irq_enable() finds a pending soft-masked interrupt, it
"replays" it by setting up registers like the initial interrupt entry,
then calls into the low level handler to set up an interrupt stack
frame and process the interrupt.

This is not necessary, and uses more stack than needed. The high level
interrupt handler can be called directly from C, with just pt_regs set
up on stack. This should be faster and use less stack.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-28-npiggin@gmail.com
2020-04-01 13:42:13 +11:00
Nicholas Piggin
68b34588e2 powerpc/64/sycall: Implement syscall entry/exit logic in C
System call entry and particularly exit code is beyond the limit of
what is reasonable to implement in asm.

This conversion moves all conditional branches out of the asm code,
except for the case that all GPRs should be restored at exit.

Null syscall test is about 5% faster after this patch, because the
exit work is handled under local_irq_disable, and the hard mask and
pending interrupt replay is handled after that, which avoids games
with MSR.

mpe: Includes subsequent fixes from Nick:

This fixes 4 issues caught by TM selftests. First was a tm-syscall bug
that hit due to tabort_syscall being called after interrupts were
reconciled (in a subsequent patch), which led to interrupts being
enabled before tabort_syscall was called. Rather than going through an
un-reconciling interrupts for the return, I just go back to putting
the test early in asm, the C-ification of that wasn't a big win
anyway.

Second is the syscall return _TIF_USER_WORK_MASK check would go into
an infinite loop if _TIF_RESTORE_TM became set. The asm code uses
_TIF_USER_WORK_MASK to brach to slowpath which includes
restore_tm_state.

Third is system call return was not calling restore_tm_state, I missed
this completely (alhtough it's in the return from interrupt C
conversion because when the asm syscall code encountered problems it
would branch to the interrupt return code.

Fourth is MSR_VEC missing from restore_math, which was caught by
tm-unavailable selftest taking an unexpected facility unavailable
interrupt when testing VSX unavailble exception with MSR.FP=1
MSR.VEC=1. Fourth case also has a fixup in a subsequent patch.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-26-npiggin@gmail.com
2020-04-01 13:42:13 +11:00
Nicholas Piggin
2babd6ea43 powerpc/64s/exception: Avoid touching the stack in hdecrementer
The hdec interrupt handler is reported to sometimes fire in Linux if
KVM leaves it pending after a guest exists. This is harmless, so there
is a no-op handler for it.

The interrupt handler currently uses the regular kernel stack. Change
this to avoid touching the stack entirely.

This should be the last place where the regular Linux stack can be
accessed with asynchronous interrupts (including PMI) soft-masked.
It might be possible to take advantage of this invariant, e.g., to
context switch the kernel stack SLB entry without clearing MSR[EE].

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-17-npiggin@gmail.com
2020-04-01 13:42:12 +11:00
Nicholas Piggin
8729c26e67 powerpc/64s/exception: Move real to virt switch into the common handler
The real mode interrupt entry points currently use rfid to branch to
the common handler in virtual mode. This is a significant amount of
code, and forces other code (notably the KVM test) to live in the
real mode handler.

In the interest of minimising the amount of code that runs unrelocated
move the switch to virt mode into the common code, and do it with
mtmsrd, which avoids clobbering SRRs (although the post-KVMTEST
performance of real-mode interrupt handlers is not a big concern these
days).

This requires CTR to always be saved (real-mode needs to reach 0xc...)
but that's not a huge impact these days. It could be optimized away in
future.

mpe: Incorporate fix from Nick:

It's possible for interrupts to be replayed when TM is enabled and
suspended, for example rt_sigreturn, where the mtmsrd MSR_KERNEL in
the real-mode entry point to the common handler causes a TM Bad Thing
exception (due to attempting to clear suspended).

The fix for this is to have replay interrupts go to the _virt entry
point and skip the mtmsrd, which matches what happens before this
patch.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225173541.1549955-11-npiggin@gmail.com
2020-04-01 13:42:11 +11:00
Paolo Bonzini
4f4af841f0 KVM PPC update for 5.7
* Add a capability for enabling secure guests under the Protected
   Execution Framework ultravisor
 
 * Various bug fixes and cleanups.
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Merge tag 'kvm-ppc-next-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

KVM PPC update for 5.7

* Add a capability for enabling secure guests under the Protected
  Execution Framework ultravisor

* Various bug fixes and cleanups.
2020-03-31 10:45:49 -04:00
Paolo Bonzini
cf39d37539 KVM/arm updates for Linux 5.7
- GICv4.1 support
 - 32bit host removal
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Merge tag 'kvmarm-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for Linux 5.7

- GICv4.1 support
- 32bit host removal
2020-03-31 10:44:53 -04:00
Thomas Gleixner
cf226c42b2 Merge branch 'uaccess.futex' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into locking/core
Pull uaccess futex cleanups for Al Viro:

     Consolidate access_ok() usage and the futex uaccess function zoo.
2020-03-28 11:59:24 +01:00
Al Viro
a08971e948 futex: arch_futex_atomic_op_inuser() calling conventions change
Move access_ok() in and pagefault_enable()/pagefault_disable() out.
Mechanical conversion only - some instances don't really need
a separate access_ok() at all (e.g. the ones only using
get_user()/put_user(), or architectures where access_ok()
is always true); we'll deal with that in followups.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-27 23:58:51 -04:00
Aneesh Kumar K.V
233ba54618 powerpc/64: Avoid isync in flush_dcache_range()
As per ISA an isync is only needed on instruction cache block
invalidate. Remove the same from dcache invalidate.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200320103242.229223-1-aneesh.kumar@linux.ibm.com
2020-03-27 17:37:07 +11:00
Ganesh Goudar
efbc4303b2 powerpc/pseries: Handle UE event for memcpy_mcsafe
memcpy_mcsafe has been implemented for power machines which is used
by pmem infrastructure, so that an UE encountered during memcpy from
pmem devices would not result in panic instead a right error code
is returned. The implementation expects machine check handler to ignore
the event and set nip to continue the execution from fixup code.

Appropriate changes are already made to powernv machine check handler,
make similar changes to pseries machine check handler to ignore the
the event and set nip to continue execution at the fixup entry if we
hit UE at an instruction with a fixup entry.

while we are at it, have a common function which searches the exception
table entry and updates nip with fixup address, and any future common
changes can be made in this function that are valid for both architectures.

powernv changes are made by
commit 895e3dceeb ("powerpc/mce: Handle UE event for memcpy_mcsafe")

Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Santosh S <santosh@fossix.org>
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200326184916.31172-1-ganeshgr@linux.ibm.com
2020-03-27 14:59:35 +11:00
Nick Desaulniers
a7032637b5 powerpc: Prefer __section and __printf from compiler_attributes.h
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
[mpe: Drop changes to a/p/boot which doesn't use linux headers]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190812215052.71840-10-ndesaulniers@google.com
2020-03-27 00:16:32 +11:00
Paul Mackerras
9a5788c615 KVM: PPC: Book3S HV: Add a capability for enabling secure guests
At present, on Power systems with Protected Execution Facility
hardware and an ultravisor, a KVM guest can transition to being a
secure guest at will.  Userspace (QEMU) has no way of knowing
whether a host system is capable of running secure guests.  This
will present a problem in future when the ultravisor is capable of
migrating secure guests from one host to another, because
virtualization management software will have no way to ensure that
secure guests only run in domains where all of the hosts can
support secure guests.

This adds a VM capability which has two functions: (a) userspace
can query it to find out whether the host can support secure guests,
and (b) userspace can enable it for a guest, which allows that
guest to become a secure guest.  If userspace does not enable it,
KVM will return an error when the ultravisor does the hypercall
that indicates that the guest is starting to transition to a
secure guest.  The ultravisor will then abort the transition and
the guest will terminate.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Ram Pai <linuxram@us.ibm.com>
2020-03-26 11:09:04 +11:00
Oliver O'Halloran
e86350f70a powerpc/eeh: Rework eeh_ops->probe()
With the EEH early probe now being pseries specific there's no need for
eeh_ops->probe() to take a pci_dn. Instead, we can make it take a pci_dev
and use the probe function to map a pci_dev to an eeh_dev. This allows
the platform to implement it's own method for finding (or creating) an
eeh_dev for a given pci_dev which also removes a use of pci_dn in
generic EEH code.

This patch also renames eeh_device_add_late() to eeh_device_probe(). This
better reflects what it does does and removes the last vestiges of the
early/late EEH probe split.

Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200306073904.4737-6-oohall@gmail.com
2020-03-25 12:09:39 +11:00
Oliver O'Halloran
b6eebb093c powerpc/eeh: Make early EEH init pseries specific
The eeh_ops->probe() function is called from two different contexts:

1. On pseries, where we set EEH_PROBE_MODE_DEVTREE, it's called in
   eeh_add_device_early() which is supposed to run before we create
   a pci_dev.

2. On PowerNV, where we set EEH_PROBE_MODE_DEV, it's called in
   eeh_device_add_late() which is supposed to run *after* the
   pci_dev is created.

The "early" probe is required because PAPR requires that we perform an RTAS
call to enable EEH support on a device before we start interacting with it
via config space or MMIO. This requirement doesn't exist on PowerNV and
shoehorning two completely separate initialisation paths into a common
interface just results in a convoluted code everywhere.

Additionally the early probe requires the probe function to take an pci_dn
rather than a pci_dev argument. We'd like to make pci_dn a pseries specific
data structure since there's no real requirement for them on PowerNV. To
help both goals move the early probe into the pseries containment zone
so the platform depedence is more explicit.

Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200306073904.4737-5-oohall@gmail.com
2020-03-25 12:09:39 +11:00
Oliver O'Halloran
2d0953f7d5 powerpc/eeh: Remove eeh_add_device_tree_late()
On pseries and PowerNV pcibios_bus_add_device() calls eeh_add_device_late()
so there's no need to do a separate tree traversal to bind the eeh_dev and
pci_dev together setting up the PHB at boot. As a result we can remove
eeh_add_device_tree_late().

Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200306073904.4737-2-oohall@gmail.com
2020-03-25 12:09:38 +11:00
Oliver O'Halloran
8645aaa879 powerpc/eeh: Add sysfs files in late probe
Move creating the EEH specific sysfs files into eeh_add_device_late()
rather than being open-coded all over the place. Calling the function is
generally done immediately after calling eeh_add_device_late() anyway. This
is also a correctness fix since currently the sysfs files will be added
even if the EEH probe happens to fail.

Similarly, on pseries we currently add the sysfs files before calling
eeh_add_device_late(). This is flat-out broken since the sysfs files
require the pci_dev->dev.archdata.edev pointer to be set, and that is done
in eeh_add_device_late().

Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200306073904.4737-1-oohall@gmail.com
2020-03-25 12:09:38 +11:00
Aneesh Kumar K.V
36b78402d9 powerpc/hash64/devmap: Use H_PAGE_THP_HUGE when setting up huge devmap PTE entries
H_PAGE_THP_HUGE is used to differentiate between a THP hugepage and
hugetlb hugepage entries. The difference is WRT how we handle hash
fault on these address. THP address enables MPSS in segments. We want
to manage devmap hugepage entries similar to THP pt entries. Hence use
H_PAGE_THP_HUGE for devmap huge PTE entries.

With current code while handling hash PTE fault, we do set is_thp =
true when finding devmap PTE huge PTE entries.

Current code also does the below sequence we setting up huge devmap
entries.

	entry = pmd_mkhuge(pfn_t_pmd(pfn, prot));
	if (pfn_t_devmap(pfn))
		entry = pmd_mkdevmap(entry);

In that case we would find both H_PAGE_THP_HUGE and PAGE_DEVMAP set
for huge devmap PTE entries. This results in false positive error like
below.

  kernel BUG at /home/kvaneesh/src/linux/mm/memory.c:4321!
  Oops: Exception in kernel mode, sig: 5 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in:
  CPU: 56 PID: 67996 Comm: t_mmap_dio Not tainted 5.6.0-rc4-59640-g371c804dedbc #128
  ....
  NIP [c00000000044c9e4] __follow_pte_pmd+0x264/0x900
  LR [c0000000005d45f8] dax_writeback_one+0x1a8/0x740
  Call Trace:
    str_spec.74809+0x22ffb4/0x2d116c (unreliable)
    dax_writeback_one+0x1a8/0x740
    dax_writeback_mapping_range+0x26c/0x700
    ext4_dax_writepages+0x150/0x5a0
    do_writepages+0x68/0x180
    __filemap_fdatawrite_range+0x138/0x180
    file_write_and_wait_range+0xa4/0x110
    ext4_sync_file+0x370/0x6e0
    vfs_fsync_range+0x70/0xf0
    sys_msync+0x220/0x2e0
    system_call+0x5c/0x68

This is because our pmd_trans_huge check doesn't exclude _PAGE_DEVMAP.

To make this all consistent, update pmd_mkdevmap to set
H_PAGE_THP_HUGE and pmd_trans_huge check now excludes _PAGE_DEVMAP
correctly.

Fixes: ebd3119793 ("powerpc/mm: Add devmap support for ppc64")
Cc: stable@vger.kernel.org # v4.13+
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200313094842.351830-1-aneesh.kumar@linux.ibm.com
2020-03-25 12:09:30 +11:00