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19754 commits

Author SHA1 Message Date
Christophe Leroy
5497c2536f powerpc: Use sizeof(struct thread_info) in INIT_SP_LIMIT
Currently INIT_SP_LIMIT uses sizeof(init_thread_info), but that symbol
won't exist when we enable THREAD_INFO_IN_TASK. So just use the sizeof
the type which is the same value but will continue to work.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
678c668a77 powerpc/64: Use task_stack_page() to initialise paca->kstack
Rather than using the thread info use task_stack_page() to initialise
paca->kstack, that way it will work with THREAD_INFO_IN_TASK.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
4e67bfd7aa powerpc: Update comments in preparation for THREAD_INFO_IN_TASK
Update a few comments that talk about current_thread_info() in
preparation for THREAD_INFO_IN_TASK.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
05b98791ec powerpc: Replace current_thread_info()->task with current
We have a few places that use current_thread_info()->task to access
current. This won't work with THREAD_INFO_IN_TASK so fix them now.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
7306e83ccf powerpc: Don't use CURRENT_THREAD_INFO to find the stack
A few places use CURRENT_THREAD_INFO, or the C version, to find the
stack. This will no longer work with THREAD_INFO_IN_TASK so change
them to find the stack in other ways.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
1e35f29c6b powerpc: call_do_[soft]irq() takes a pointer to the stack
The purpose of the pointer given to call_do_softirq() and
call_do_irq() is to point the new stack. Currently that's the same
thing as the thread_info, but won't be with THREAD_INFO_IN_TASK.

So change the parameter to void* and rename it 'sp'.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
8c1fc5abdc powerpc: Rename THREAD_INFO to TASK_STACK
This patch renames THREAD_INFO to TASK_STACK, because it is in fact
the offset of the pointer to the stack in task_struct so this pointer
will not be impacted by the move of THREAD_INFO.

Also make it available on 64-bit, as we'll need it there when we
activate THREAD_INFO_IN_TASK.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Make available on 64-bit]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
018cce33c5 powerpc: prep stack walkers for THREAD_INFO_IN_TASK
[text copied from commit 9bbd4c56b0
("arm64: prep stack walkers for THREAD_INFO_IN_TASK")]

When CONFIG_THREAD_INFO_IN_TASK is selected, task stacks may be freed
before a task is destroyed. To account for this, the stacks are
refcounted, and when manipulating the stack of another task, it is
necessary to get/put the stack to ensure it isn't freed and/or re-used
while we do so.

This patch reworks the powerpc stack walking code to account for this.
When CONFIG_THREAD_INFO_IN_TASK is not selected these perform no
refcounting, and this should only be a structural change that does not
affect behaviour.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Move try_get_task_stack() below tsk == NULL check in show_stack()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
054860897c powerpc: Only use task_struct 'cpu' field on SMP
When moving to CONFIG_THREAD_INFO_IN_TASK, the thread_info 'cpu' field
gets moved into task_struct and only defined when CONFIG_SMP is set.

This patch ensures that TI_CPU is only used when CONFIG_SMP is set and
that task_struct 'cpu' field is not used directly out of SMP code.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Christophe Leroy
92ab45c5f2 powerpc: Avoid circular header inclusion in mmu-hash.h
When activating CONFIG_THREAD_INFO_IN_TASK, linux/sched.h includes
asm/current.h. This generates a circular dependency. To avoid that,
asm/processor.h shall not be included in mmu-hash.h.

In order to do that, this patch moves into a new header called
asm/task_size_64/32.h all the TASK_SIZE related constants, which can
then be included in mmu-hash.h directly.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out all the TASK_SIZE constants not just 64-bit ones]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Christophe Leroy
c8e409a33c powerpc/irq: use memblock functions returning virtual address
Since only the virtual address of allocated blocks is used,
lets use functions returning directly virtual address.

Those functions have the advantage of also zeroing the block.

Suggested-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Michael Ellerman
eafd825ed7 powerpc/64: Simplify __secondary_start paca->kstack handling
In __secondary_start() we load the thread_info of the idle task of the
secondary CPU from current_set[cpu], and then convert it into a stack
pointer before storing that back to paca->kstack.

As pointed out in commit f761622e59 ("powerpc: Initialise
paca->kstack before early_setup_secondary") it's important that we
initialise paca->kstack before calling the MMU setup code, in
particular slb_initialize(), because it will bolt the SLB entry for
the kstack into the SLB.

However we have already setup paca->kstack in cpu_idle_thread_init(),
since commit 3b5750644b ("[POWERPC] Bolt in SLB entry for kernel
stack on secondary cpus") (May 2008).

It's also in cpu_idle_thread_init() that we initialise current_set[cpu]
with the thread_info pointer, so there is no issue of the timing being
different between the two.

Therefore the initialisation of paca->kstack in __setup_secondary() is
completely redundant, so remove it.

This has the added benefit of removing code that runs in real mode,
and is therefore restricted by the RMO, and so opens the way for us to
enable THREAD_INFO_IN_TASK.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Michael Ellerman
e7fda7e569 powerpc/64s: Remove MSR_RI optimisation in system_call_exit()
Currently in system_call_exit() we have an optimisation where we
disable MSR_RI (recoverable interrupt) and MSR_EE (external interrupt
enable) in a single mtmsrd instruction.

Unfortunately this will no longer work with THREAD_INFO_IN_TASK,
because then the load of TI_FLAGS might fault and faulting with MSR_RI
clear is treated as an unrecoverable exception which leads to a
panic().

So change the code to only clear MSR_EE prior to loading TI_FLAGS,
leaving the clear of MSR_RI until later. We have some latitude in
where do the clear of MSR_RI. A bit of experimentation has shown that
this location gives the least slow down.

This still causes a noticeable slow down in our null_syscall
performance. On a Power9 DD2.2:

  Before        After         Delta     Delta %
  955 cycles    999 cycles    -44	-4.6%

On the plus side this does simplify the code somewhat, because we
don't have to reenable MSR_RI on the restore_math() or
syscall_exit_work() paths which was necessitated previously by the
optimisation.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Andrew Donnellan
fb0b0a73b2 powerpc: Enable kcov
kcov provides kernel coverage data that's useful for fuzzing tools like
syzkaller.

Wire up kcov support on powerpc. Disable kcov instrumentation on the same
files where we currently disable gcov and UBSan instrumentation, plus some
additional exclusions which appear necessary to boot on book3e machines.

Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Daniel Axtens <dja@axtens.net> # e6500
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
8f54a6f740 powerpc/kconfig: make _etext and data areas alignment configurable on 8xx
On 8xx, large pages (512kb or 8M) are used to map kernel linear
memory. Aligning to 8M reduces TLB misses as only 8M pages are used
in that case. We make 8M the default for data.

This patchs allows the user to do it via Kconfig.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
d5f17ee964 powerpc/8xx: don't disable large TLBs with CONFIG_STRICT_KERNEL_RWX
This patch implements handling of STRICT_KERNEL_RWX with
large TLBs directly in the TLB miss handlers.

To do so, etext and sinittext are aligned on 512kB boundaries
and the miss handlers use 512kB pages instead of 8Mb pages for
addresses close to the boundaries.

It sets RO PP flags for addresses under sinittext.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
0f4a9041c7 powerpc/kconfig: make _etext and data areas alignment configurable on Book3s 32
Depending on the number of available BATs for mapping the different
kernel areas, it might be needed to increase the alignment of _etext
and/or of data areas.

This patchs allows the user to do it via Kconfig.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
63b2bc6195 powerpc/mm/32s: Use BATs for STRICT_KERNEL_RWX
Today, STRICT_KERNEL_RWX is based on the use of regular pages
to map kernel pages.

On Book3s 32, it has three consequences:
- Using pages instead of BAT for mapping kernel linear memory severely
impacts performance.
- Exec protection is not effective because no-execute cannot be set at
page level (except on 603 which doesn't have hash tables)
- Write protection is not effective because PP bits do not provide RO
mode for kernel-only pages (except on 603 which handles it in software
via PAGE_DIRTY)

On the 603+, we have:
- Independent IBAT and DBAT allowing limitation of exec parts.
- NX bit can be set in segment registers to forbit execution on memory
mapped by pages.
- RO mode on DBATs even for kernel-only blocks.

On the 601, there is nothing much we can do other than warn the user
about it, because:
- BATs are common to instructions and data.
- BAT do not provide RO mode for kernel-only blocks.
- segment registers don't have the NX bit.

In order to use IBAT for exec protection, this patch:
- Aligns _etext to BAT block sizes (128kb)
- Set NX bit in kernel segment register (Except on vmalloc area when
CONFIG_MODULES is selected)
- Maps kernel text with IBATs.

In order to use DBAT for exec protection, this patch:
- Aligns RW DATA to BAT block sizes (4M)
- Maps kernel RO area with write prohibited DBATs
- Maps remaining memory with remaining DBATs

Here is what we get with this patch on a 832x when activating
STRICT_KERNEL_RWX:

Symbols:
c0000000 T _stext
c0680000 R __start_rodata
c0680000 R _etext
c0800000 T __init_begin
c0800000 T _sinittext

~# cat /sys/kernel/debug/block_address_translation
---[ Instruction Block Address Translation ]---
0: 0xc0000000-0xc03fffff 0x00000000 Kernel EXEC coherent
1: 0xc0400000-0xc05fffff 0x00400000 Kernel EXEC coherent
2: 0xc0600000-0xc067ffff 0x00600000 Kernel EXEC coherent
3:         -
4:         -
5:         -
6:         -
7:         -

---[ Data Block Address Translation ]---
0: 0xc0000000-0xc07fffff 0x00000000 Kernel RO coherent
1: 0xc0800000-0xc0ffffff 0x00800000 Kernel RW coherent
2: 0xc1000000-0xc1ffffff 0x01000000 Kernel RW coherent
3: 0xc2000000-0xc3ffffff 0x02000000 Kernel RW coherent
4: 0xc4000000-0xc7ffffff 0x04000000 Kernel RW coherent
5: 0xc8000000-0xcfffffff 0x08000000 Kernel RW coherent
6: 0xd0000000-0xdfffffff 0x10000000 Kernel RW coherent
7:         -

~# cat /sys/kernel/debug/segment_registers
---[ User Segments ]---
0x00000000-0x0fffffff Kern key 1 User key 1 VSID 0xa085d0
0x10000000-0x1fffffff Kern key 1 User key 1 VSID 0xa086e1
0x20000000-0x2fffffff Kern key 1 User key 1 VSID 0xa087f2
0x30000000-0x3fffffff Kern key 1 User key 1 VSID 0xa08903
0x40000000-0x4fffffff Kern key 1 User key 1 VSID 0xa08a14
0x50000000-0x5fffffff Kern key 1 User key 1 VSID 0xa08b25
0x60000000-0x6fffffff Kern key 1 User key 1 VSID 0xa08c36
0x70000000-0x7fffffff Kern key 1 User key 1 VSID 0xa08d47
0x80000000-0x8fffffff Kern key 1 User key 1 VSID 0xa08e58
0x90000000-0x9fffffff Kern key 1 User key 1 VSID 0xa08f69
0xa0000000-0xafffffff Kern key 1 User key 1 VSID 0xa0907a
0xb0000000-0xbfffffff Kern key 1 User key 1 VSID 0xa0918b

---[ Kernel Segments ]---
0xc0000000-0xcfffffff Kern key 0 User key 1 No Exec VSID 0x000ccc
0xd0000000-0xdfffffff Kern key 0 User key 1 No Exec VSID 0x000ddd
0xe0000000-0xefffffff Kern key 0 User key 1 No Exec VSID 0x000eee
0xf0000000-0xffffffff Kern key 0 User key 1 No Exec VSID 0x000fff

Aligning _etext to 128kb allows to map up to 32Mb text with 8 IBATs:
16Mb + 8Mb + 4Mb + 2Mb + 1Mb + 512kb + 256kb + 128kb (+ 128kb) = 32Mb
(A 9th IBAT is unneeded as 32Mb would need only a single 32Mb block)

Aligning data to 4M allows to map up to 512Mb data with 8 DBATs:
16Mb + 8Mb + 4Mb + 4Mb + 32Mb + 64Mb + 128Mb + 256Mb = 512Mb

Because some processors only have 4 BATs and because some targets need
DBATs for mapping other areas, the following patch will allow to
modify _etext and data alignment.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
5e04ae85fb powerpc/mm/32s: add setibat() clearibat() and update_bats()
setibat() and clearibat() allows to manipulate IBATs independently
of DBATs.

update_bats() allows to update bats after init. This is done
with MMU off.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
166d97d961 powerpc/kconfig: define CONFIG_DATA_SHIFT and CONFIG_ETEXT_SHIFT
CONFIG_STRICT_KERNEL_RWX requires a special alignment
for DATA for some subarches. Today it is just defined
as an #ifdef in vmlinux.lds.S

In order to get more flexibility, this patch moves the
definition of this alignment in Kconfig

On some subarches, CONFIG_STRICT_KERNEL_RWX will
require a special alignment of _etext.

This patch also adds a configuration item for it in Kconfig

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
555f4fdb93 powerpc/kconfig: define PAGE_SHIFT inside Kconfig
This patch defined CONFIG_PPC_PAGE_SHIFT in order
to be able to use PAGE_SHIFT value inside Kconfig.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
28ea38b9cb powerpc/mmu: add is_strict_kernel_rwx() helper
Add a helper to know whether STRICT_KERNEL_RWX is enabled.

This is based on rodata_enabled flag which is defined only
when CONFIG_STRICT_KERNEL_RWX is selected.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
02d5d13b45 powerpc/32: add helper to write into segment registers
This patch add an helper which wraps 'mtsrin' instruction
to write into segment registers.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
df25f86390 powerpc/mm/32s: use _PAGE_EXEC in setbat()
Do not set IBAT when setbat() is called without _PAGE_EXEC

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
160985f302 powerpc/wii: remove wii_mmu_mapin_mem2()
wii_mmu_mapin_mem2() is not used anymore, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
d2f15e0979 powerpc/32: always populate page tables for Abatron BDI.
When CONFIG_BDI_SWITCH is set, the page tables have to be populated
allthough large TLBs are used, because the BDI switch knows nothing
about those large TLBs which are handled directly in TLB miss logic.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
9e849f231c powerpc/mm/32s: use generic mmu_mapin_ram() for all blocks.
Now that mmu_mapin_ram() is able to handle other blocks
than the one starting at 0, the WII can use it for all
its blocks.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:32 +11:00
Christophe Leroy
e4d6654ebe powerpc/mm/32s: rework mmu_mapin_ram()
This patch reworks mmu_mapin_ram() to be more generic and map as much
blocks as possible. It now supports blocks not starting at address 0.

It scans DBATs array to find free ones instead of forcing the use of
BAT2 and BAT3.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Christophe Leroy
14e609d693 powerpc/mm/32: add base address to mmu_mapin_ram()
At the time being, mmu_mapin_ram() always maps RAM from the beginning.
But some platforms like the WII have to map a second block of RAM.

This patch adds to mmu_mapin_ram() the base address of the block.
At the moment, only base address 0 is supported.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Christophe Leroy
6d183ca8ba powerpc/wii: properly disable use of BATs when requested.
'nobats' kernel parameter or some options like CONFIG_DEBUG_PAGEALLOC
deny the use of BATS for mapping memory.

This patch makes sure that the specific wii RAM mapping function
takes it into account as well.

Fixes: de32400dd2 ("wii: use both mem1 and mem2 as ram")
Cc: stable@vger.kernel.org
Reviewed-by: Jonathan Neuschafer <j.neuschaefer@gmx.net>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Christophe Leroy
e4470bd6a4 powerpc/8xx: Map 32Mb of RAM at init.
At the time being, initial MMU setup allows 24 Mbytes
of DATA and 8 Mbytes of code.

Some debug setup like CONFIG_KASAN generate huge
kernels with text size over the 8M limit and data over the
24 Mbytes limit.

Here is an 8xx kernel compiled with CONFIG_KASAN_INLINE for
one of my boards:

[root@po16846vm linux-powerpc]# size -x vmlinux
   text	   data	    bss	    dec	    hex	filename
0x111019c	0x41b0d4	0x490de0	26984528	19bc050	vmlinux

This patch maps up to 32 Mbytes code based on _einittext symbol
and allows 32 Mbytes of memory instead of 24.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Christophe Leroy
665bed2386 powerpc/8xx: replace most #ifdef by IS_ENABLED() in 8xx_mmu.c
This patch replaces most #ifdef mess by IS_ENABLED() in 8xx_mmu.c
This has the advantage of allowing syntax verification at compile
time regardless of selected options.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Sandipan Das
78a8da0600 powerpc: sstep: Add tests for addc[.] instruction
This adds test cases for the addc[.] instruction.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Sandipan Das
44dea1784b powerpc: sstep: Add tests for add[.] instruction
This adds test cases for the add[.] instruction.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Sandipan Das
84022ac173 powerpc: sstep: Add tests for compute type instructions
This enhances the current selftest framework for validating
the in-kernel instruction emulation infrastructure by adding
support for compute type instructions i.e. integer ALU-based
instructions. Originally, this framework was limited to only
testing load and store instructions.

While most of the GPRs can be validated, support for SPRs is
limited to LR, CR and XER for now.

When writing the test cases, one must ensure that the Stack
Pointer (GPR1) or the Thread Pointer (GPR13) are not touched
by any means as these are vital non-volatile registers.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
[mpe: Use patch_site for the code patching]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 21:04:31 +11:00
Michael Ellerman
f68e792721 Revert "powerpc/book3s32: Reorder _PAGE_XXX flags to simplify TLB handling"
This reverts commit 78ca1108b1.

It is causing boot failures with qemu mac99 in at least some
configurations.
2019-02-23 20:30:50 +11:00
Paolo Bonzini
54a1f393ce PPC KVM update for 5.1
There are no major new features this time, just a collection of bug
 fixes and improvements in various areas, including machine check
 handling and context switching of protection-key-related registers.
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Merge tag 'kvm-ppc-next-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-next

PPC KVM update for 5.1

There are no major new features this time, just a collection of bug
fixes and improvements in various areas, including machine check
handling and context switching of protection-key-related registers.
2019-02-22 17:43:05 +01:00
Christophe Leroy
e66c3209c7 powerpc: Move page table dump files in a dedicated subdirectory
This patch moves the files related to page table dump in a
dedicated subdirectory.

The purpose is to clean a bit arch/powerpc/mm by regrouping
multiple files handling a dedicated function.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Shorten the file names while we're at it]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 22:29:22 +11:00
Paul Mackerras
0a0c50f771 Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-next
This merges in the "ppc-kvm" topic branch of the powerpc tree to get a
series of commits that touch both general arch/powerpc code and KVM
code.  These commits will be merged both via the KVM tree and the
powerpc tree.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-22 13:52:30 +11:00
Michael Ellerman
c3c7470c75 powerpc/kvm: Save and restore host AMR/IAMR/UAMOR
When the hash MMU is active the AMR, IAMR and UAMOR are used for
pkeys. The AMR is directly writable by user space, and the UAMOR masks
those writes, meaning both registers are effectively user register
state. The IAMR is used to create an execute only key.

Also we must maintain the value of at least the AMR when running in
process context, so that any memory accesses done by the kernel on
behalf of the process are correctly controlled by the AMR.

Although we are correctly switching all registers when going into a
guest, on returning to the host we just write 0 into all regs, except
on Power9 where we restore the IAMR correctly.

This could be observed by a user process if it writes the AMR, then
runs a guest and we then return immediately to it without
rescheduling. Because we have written 0 to the AMR that would have the
effect of granting read/write permission to pages that the process was
trying to protect.

In addition, when using the Radix MMU, the AMR can prevent inadvertent
kernel access to userspace data, writing 0 to the AMR disables that
protection.

So save and restore AMR, IAMR and UAMOR.

Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-22 13:41:13 +11:00
Alexey Kardashevskiy
716cb11608 KVM: PPC: Book3S: Improve KVM reference counting
The anon fd's ops releases the KVM reference in the release hook.
However we reference the KVM object after we create the fd so there is
small window when the release function can be called and
dereferenced the KVM object which potentially may free it.

It is not a problem at the moment as the file is created and KVM is
referenced under the KVM lock and the release function obtains the same
lock before dereferencing the KVM (although the lock is not held when
calling kvm_put_kvm()) but it is potentially fragile against future changes.

This references the KVM object before creating a file.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-22 12:51:02 +11:00
Jordan Niethe
e40542aff9 KVM: PPC: Book3S HV: Fix build failure without IOMMU support
Currently trying to build without IOMMU support will fail:

  (.text+0x1380): undefined reference to `kvmppc_h_get_tce'
  (.text+0x1384): undefined reference to `kvmppc_rm_h_put_tce'
  (.text+0x149c): undefined reference to `kvmppc_rm_h_stuff_tce'
  (.text+0x14a0): undefined reference to `kvmppc_rm_h_put_tce_indirect'

This happens because turning off IOMMU support will prevent
book3s_64_vio_hv.c from being built because it is only built when
SPAPR_TCE_IOMMU is set, which depends on IOMMU support.

Fix it using ifdefs for the undefined references.

Fixes: 76d837a4c0 ("KVM: PPC: Book3S PR: Don't include SPAPR TCE code on non-pseries platforms")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-02-22 12:51:02 +11:00
Christophe Leroy
cabe8138b2 powerpc: dump as a single line areas mapping a single physical page.
When using KASAN, there are parts of the shadow area where all
pages are mapped to the kasan_early_shadow_page. It is pointless
to dump one line for each of those pages (in the example below there
are 7168 entries pointing to the same physical page).

~# cat /sys/kernel/debug/kernel_page_tables
 ...
---[ kasan shadow mem start ]---
0xf7c00000-0xf8bfffff 0x06fac000       16M        rw       present           dirty  accessed
0xf8c00000-0xf8c03fff 0x00cd0000       16K        r        present           dirty  accessed
0xf8c04000-0xf8c07fff 0x00cd0000       16K        r        present           dirty  accessed
0xf8c08000-0xf8c0bfff 0x00cd0000       16K        r        present           dirty  accessed
0xf8c0c000-0xf8c0ffff 0x00cd0000       16K        r        present           dirty  accessed
0xf8c10000-0xf8c13fff 0x00cd0000       16K        r        present           dirty  accessed
 ... 7168 identical lines
0xffbfc000-0xffbfffff 0x00cd0000       16K        r        present           dirty  accessed
---[ kasan shadow mem end ]---
 ...

This patch modifies linux table dump to dump as a single line areas
where all addresses points to the same physical page. That physical
address is put inside [] to show that all virt pages points to the
same phys page.

~# cat /sys/kernel/debug/kernel_page_tables
 ...
---[ kasan shadow mem start ]---
0xf7c00000-0xf8bfffff  0x06fac000        16M        rw       present           dirty  accessed
0xf8c00000-0xffbfffff [0x00cd0000]       16K        r        present           dirty  accessed
---[ kasan shadow mem end ]---
 ...

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
6b9166f078 powerpc/32: Fix CONFIG_VIRT_CPU_ACCOUNTING_NATIVE for 40x/booke
40x/booke have another path to reach 3f from transfer_to_handler,
make sure it also calls ACCOUNT_CPU_USER_ENTRY() when
CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is selected.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
78ca1108b1 powerpc/book3s32: Reorder _PAGE_XXX flags to simplify TLB handling
For pages without _PAGE_USER, PP field is 00
For pages with _PAGE_USER, PP field is 10 for RW and 11 for RO.

This patch sets _PAGE_USER to 0x002 and _PAGE_RW to 0x001
is order to simplify TLB handling by reducing amount of shifts.

The location of _PAGE_PRESENT and _PAGE_HASHPTE doesn't matter
as they are only SW related flags.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
84de6ab0e9 powerpc/603: don't handle PAGE_ACCESSED in TLB miss handlers.
PAGE_ACCESSED is only needed for CONFIG_SWAP. When CONFIG_SWAP
is not set, just ignore it. If CONFIG_SWAP is set and PAGE_ACCESSED
is not, let's take a minor fault.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
451b3ec082 powerpc/603: Don't worry about _PAGE_USER in TLB miss handlers
PP bits take user access into account, so no need to check _PAGE_USER
here. A DSI or ISI will be generated if needed.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
f8b58c64ea powerpc/603: let's handle PAGE_DIRTY directly
PAGE_DIRTY corresponds to the C bit. If writing on
a page for which the C bit is not set, a DataStoreTLBMiss
is generated. No need to check it in DataLoadTLBMiss.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
54a05a30c8 powerpc/603: Don't handle _PAGE_RW and _PAGE_DIRTY on ITLB misses
_PAGE_RW and _PAGE_DIRTY do not matter for ITLB misses.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
a8a121995b powerpc/603: Don't handle kernel page TLB misses when not need
ITLB miss on kernel pages only occur with CONFIG_MODULES and
CONFIG_DEBUG_PAGEALLOC.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00