diff options
| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2019-01-31 11:08:58 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-02-23 12:31:40 +0100 |
| commit | ed1cd6deb013a11959d17a94e35ce159197632da (patch) | |
| tree | fcfdc0de67e7753db653d06938d939fa0f0e924f /arch/powerpc/kernel/exceptions-64e.S | |
| parent | powerpc/idle/6xx: Use r1 with CURRENT_THREAD_INFO() (diff) | |
| download | linux-ed1cd6deb013a11959d17a94e35ce159197632da.tar.xz 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/exceptions-64e.S')
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64e.S | 11 |
1 files changed, 0 insertions, 11 deletions
diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index afb638778f44..20f14996281d 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -77,17 +77,6 @@ special_reg_save: andi. r3,r3,MSR_PR bnelr - /* Copy info into temporary exception thread info */ - ld r11,PACAKSAVE(r13) - CURRENT_THREAD_INFO(r11, r11) - CURRENT_THREAD_INFO(r12, r1) - ld r10,TI_FLAGS(r11) - std r10,TI_FLAGS(r12) - ld r10,TI_PREEMPT(r11) - std r10,TI_PREEMPT(r12) - ld r10,TI_TASK(r11) - std r10,TI_TASK(r12) - /* * Advance to the next TLB exception frame for handler * types that don't do it automatically. |