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| author | Michael Ellerman <mpe@ellerman.id.au> | 2024-08-23 09:08:30 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2024-09-05 14:30:05 +0200 |
| commit | 29dbb984496daa490f3c1181b734b538a6f7b534 (patch) | |
| tree | 04ac34f19e0c9aec73d749f0a371372d41a30b45 /arch | |
| parent | powerpc/mm/64s: Restrict THP to Radix or HPT w/64K pages (diff) | |
| download | linux-29dbb984496daa490f3c1181b734b538a6f7b534.tar.xz linux-29dbb984496daa490f3c1181b734b538a6f7b534.zip | |
powerpc/64s: Remove the "fast endian switch" syscall
The non-standard "fast endian switch" syscall was added in 2008[1],
but was never widely used. It was disabled by default in 2017[2], and
there's no evidence it's ever been used since.
Remove it entirely.
A normal endian switch syscall was added in 2015[3].
[1]: 745a14cc264b ("[POWERPC] Add fast little-endian switch system call")
[2]: 529d235a0e19 ("powerpc: Add a proper syscall for switching endianness")
[3]: 727f13616c45 ("powerpc: Disable the fast-endian switch syscall by default")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240823070830.1269033-1-mpe@ellerman.id.au
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/Kconfig.debug | 6 | ||||
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 17 |
2 files changed, 0 insertions, 23 deletions
diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index 3799ceceb04a..0bbec4afc0d5 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -379,12 +379,6 @@ config FAIL_IOMMU If you are unsure, say N. -config PPC_FAST_ENDIAN_SWITCH - bool "Deprecated fast endian-switch syscall" - depends on DEBUG_KERNEL && PPC_BOOK3S_64 - help - If you're unsure what this is, say N. - config KASAN_SHADOW_OFFSET hex depends on KASAN diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index eaf2f167c342..195b075d116c 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -1989,13 +1989,6 @@ INT_DEFINE_END(system_call) INTERRUPT_TO_KERNEL #endif -#ifdef CONFIG_PPC_FAST_ENDIAN_SWITCH -BEGIN_FTR_SECTION - cmpdi r0,0x1ebe - beq- 1f -END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) -#endif - /* We reach here with PACA in r13, r13 in r9. */ mfspr r11,SPRN_SRR0 mfspr r12,SPRN_SRR1 @@ -2015,16 +2008,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) b system_call_common #endif .endif - -#ifdef CONFIG_PPC_FAST_ENDIAN_SWITCH - /* Fast LE/BE switch system call */ -1: mfspr r12,SPRN_SRR1 - xori r12,r12,MSR_LE - mtspr SPRN_SRR1,r12 - mr r13,r9 - RFI_TO_USER /* return to userspace */ - b . /* prevent speculative execution */ -#endif .endm EXC_REAL_BEGIN(system_call, 0xc00, 0x100) |