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| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2020-01-07 10:16:40 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-02-26 00:34:40 +0100 |
| commit | 05642cf7289c5562e5939d2ee8a0529d310010b8 (patch) | |
| tree | 1e344c650300f74315dc9dac641cba78601a170a | |
| parent | powerpc/32s: Slenderize _tlbia() for powerpc 603/603e (diff) | |
| download | linux-05642cf7289c5562e5939d2ee8a0529d310010b8.tar.xz linux-05642cf7289c5562e5939d2ee8a0529d310010b8.zip | |
powerpc/32: don't restore r0, r6-r8 on exception entry path after trace_hardirqs_off()
Since commit b86fb88855ea ("powerpc/32: implement fast entry for
syscalls on non BOOKE") and commit 1a4b739bbb4f ("powerpc/32:
implement fast entry for syscalls on BOOKE"), syscalls don't
use the exception entry path anymore. It is therefore pointless
to restore r0 and r6-r8 after calling trace_hardirqs_off().
In the meantime, drop the '2:' label which is unused and misleading.
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/d2c6dc65d27e83964eb05f16a126161ab6455eea.1578388585.git.christophe.leroy@c-s.fr
| -rw-r--r-- | arch/powerpc/kernel/entry_32.S | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index ad000cbb5252..afab378c3d28 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -246,9 +246,8 @@ reenable_mmu: * r3 can be different from GPR3(r1) at this point, r9 and r11 * contains the old MSR and handler address respectively, * r4 & r5 can contain page fault arguments that need to be passed - * along as well. r12, CCR, CTR, XER etc... are left clobbered as - * they aren't useful past this point (aren't syscall arguments), - * the rest is restored from the exception frame. + * along as well. r0, r6-r8, r12, CCR, CTR, XER etc... are left + * clobbered as they aren't useful past this point. */ stwu r1,-32(r1) @@ -262,16 +261,12 @@ reenable_mmu: * lockdep */ 1: bl trace_hardirqs_off -2: lwz r5,24(r1) + lwz r5,24(r1) lwz r4,20(r1) lwz r3,16(r1) lwz r11,12(r1) lwz r9,8(r1) addi r1,r1,32 - lwz r0,GPR0(r1) - lwz r6,GPR6(r1) - lwz r7,GPR7(r1) - lwz r8,GPR8(r1) mtctr r11 mtlr r9 bctr /* jump to handler */ |