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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2021-02-08 18:10:34 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-02-11 15:35:11 +0300 |
| commit | 4d67facbcbdb3d9e3c9cb82e4ec47fc63d298dd8 (patch) | |
| tree | bc4fcd1888bd1bd6089c5d72bd3200f800cb2340 /arch/powerpc/kernel/entry_32.S | |
| parent | 6f76a01173ccaa363739f913394d4e138d92d718 (diff) | |
| download | linux-4d67facbcbdb3d9e3c9cb82e4ec47fc63d298dd8.tar.xz | |
powerpc/32: Remove verification of MSR_PR on syscall in the ASM entry
system_call_exception() checks MSR_PR and BUGs if a syscall
is issued from kernel mode.
No need to handle it anymore from the ASM entry code.
null_syscall reduction 2 cycles (348 => 346 cycles)
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1eddb42cb12092b1e3d72608d182c365db3da41d.1612796617.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/kernel/entry_32.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_32.S | 30 |
1 files changed, 0 insertions, 30 deletions
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index bbf7ecea6fe0..cffe58e63356 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -421,36 +421,6 @@ ret_from_kernel_thread: li r3,0 b ret_from_syscall - /* - * System call was called from kernel. We get here with SRR1 in r9. - * Mark the exception as recoverable once we have retrieved SRR0, - * trap a warning and return ENOSYS with CR[SO] set. - */ - .globl ret_from_kernel_syscall -ret_from_kernel_syscall: - mfspr r9, SPRN_SRR0 - mfspr r10, SPRN_SRR1 -#if !defined(CONFIG_4xx) && !defined(CONFIG_BOOKE) - LOAD_REG_IMMEDIATE(r11, MSR_KERNEL & ~(MSR_IR|MSR_DR)) - mtmsr r11 -#endif - -0: trap - EMIT_BUG_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING - - li r3, ENOSYS - crset so -#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS) - mtspr SPRN_NRI, r0 -#endif - mtspr SPRN_SRR0, r9 - mtspr SPRN_SRR1, r10 - rfi -#ifdef CONFIG_40x - b . /* Prevent prefetch past rfi */ -#endif -_ASM_NOKPROBE_SYMBOL(ret_from_kernel_syscall) - /* * Top-level page fault handling. * This is in assembler because if do_page_fault tells us that |