From dd7b2f035ec41a409f7a7cec7aabc0ec0eacf476 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Tue, 29 Nov 2016 13:13:46 +1100 Subject: [PATCH] powerpc/mm: Fix lazy icache flush on pre-POWER5 On 64-bit CPUs with no-execute support and non-snooping icache, such as 970 or POWER4, we have a software mechanism to ensure coherency of the cache (using exec faults when needed). This was broken due to a logic error when the code was rewritten from assembly to C, previously the assembly code did: BEGIN_FTR_SECTION mr r4,r30 mr r5,r7 bl hash_page_do_lazy_icache END_FTR_SECTION(CPU_FTR_NOEXECUTE|CPU_FTR_COHERENT_ICACHE, CPU_FTR_NOEXECUTE) Which tests that: (cpu_features & (NOEXECUTE | COHERENT_ICACHE)) == NOEXECUTE Which says that the current cpu does have NOEXECUTE, but does not have COHERENT_ICACHE. Fixes: 91f1da99792a ("powerpc/mm: Convert 4k hash insert to C") Fixes: 89ff725051d1 ("powerpc/mm: Convert __hash_page_64K to C") Fixes: a43c0eb8364c ("powerpc/mm: Convert 4k insert from asm to C") Cc: stable@vger.kernel.org # v4.5+ Signed-off-by: Benjamin Herrenschmidt Reviewed-by: Aneesh Kumar K.V [mpe: Change log verbosification] Signed-off-by: Michael Ellerman --- arch/powerpc/mm/hash64_4k.c | 2 +- arch/powerpc/mm/hash64_64k.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c index 42c702b..6fa450c 100644 --- a/arch/powerpc/mm/hash64_4k.c +++ b/arch/powerpc/mm/hash64_4k.c @@ -55,7 +55,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid, */ rflags = htab_convert_pte_flags(new_pte); - if (!cpu_has_feature(CPU_FTR_NOEXECUTE) && + if (cpu_has_feature(CPU_FTR_NOEXECUTE) && !cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap); diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c index 3bbbea0..1a68cb1 100644 --- a/arch/powerpc/mm/hash64_64k.c +++ b/arch/powerpc/mm/hash64_64k.c @@ -87,7 +87,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid, subpg_pte = new_pte & ~subpg_prot; rflags = htab_convert_pte_flags(subpg_pte); - if (!cpu_has_feature(CPU_FTR_NOEXECUTE) && + if (cpu_has_feature(CPU_FTR_NOEXECUTE) && !cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) { /* @@ -258,7 +258,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access, rflags = htab_convert_pte_flags(new_pte); - if (!cpu_has_feature(CPU_FTR_NOEXECUTE) && + if (cpu_has_feature(CPU_FTR_NOEXECUTE) && !cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap); -- 2.7.4