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| author |  Christophe Leroy <christophe.leroy@c-s.fr>
| 2019-01-31 10:08:58 +0000 |
|---|---|---|
| committer |  Michael Ellerman <mpe@ellerman.id.au>
| 2019-02-23 22:31:40 +1100 |
| commit | ed1cd6deb013a11959d17a94e35ce159197632da (patch) | |
| tree | fcfdc0de67e7753db653d06938d939fa0f0e924f /arch/powerpc/kernel/head_booke.h | |
| parent | powerpc/idle/6xx: Use r1 with CURRENT_THREAD_INFO() (diff) | |
| download | linux-ed1cd6deb013a11959d17a94e35ce159197632da.tar.gz linux-ed1cd6deb013a11959d17a94e35ce159197632da.tar.bz2 linux-ed1cd6deb013a11959d17a94e35ce159197632da.zip | |
powerpc: Activate CONFIG_THREAD_INFO_IN_TASK
This patch activates CONFIG_THREAD_INFO_IN_TASK which
moves the thread_info into task_struct.
Moving thread_info into task_struct has the following advantages:
- It protects thread_info from corruption in the case of stack
overflows.
- Its address is harder to determine if stack addresses are leaked,
making a number of attacks more difficult.
This has the following consequences:
- thread_info is now located at the beginning of task_struct.
- The 'cpu' field is now in task_struct, and only exists when
CONFIG_SMP is active.
- thread_info doesn't have anymore the 'task' field.
This patch:
- Removes all recopy of thread_info struct when the stack changes.
- Changes the CURRENT_THREAD_INFO() macro to point to current.
- Selects CONFIG_THREAD_INFO_IN_TASK.
- Modifies raw_smp_processor_id() to get ->cpu from current without
including linux/sched.h to avoid circular inclusion and without
including asm/asm-offsets.h to avoid symbol names duplication
between ASM constants and C constants.
- Modifies klp_init_thread_info() to take a task_struct pointer
argument.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add task_stack.h to livepatch.h to fix build fails]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/head_booke.h')
| -rw-r--r-- | arch/powerpc/kernel/head_booke.h | 8 |
1 files changed, 1 insertions, 7 deletions
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h index 69e80e6d0d16..1b22a8dea399 100644 --- a/arch/powerpc/kernel/head_booke.h +++ b/arch/powerpc/kernel/head_booke.h @@ -155,13 +155,7 @@ END_BTB_FLUSH_SECTION stw r10,GPR11(r11); \ b 2f; \ /* COMING FROM PRIV MODE */ \ -1: lwz r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r11); \ - lwz r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r11); \ - stw r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r8); \ - stw r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r8); \ - lwz r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r11); \ - stw r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r8); \ - mr r11,r8; \ +1: mr r11, r8; \ 2: mfspr r8,SPRN_SPRG_RSCRATCH_##exc_level; \ stw r12,GPR12(r11); /* save various registers */\ mflr r10; \ |