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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2016-11-29 13:13:46 +1100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-11-29 23:59:40 +1100 |
| commit | dd7b2f035ec41a409f7a7cec7aabc0ec0eacf476 (patch) | |
| tree | 85a1f8572cf685f2ed708b4ad61584b4a44a1846 /arch/powerpc/mm/hash64_4k.c | |
| parent | 10c77dba40ff58fc03587b3b60725bb7fd723183 (diff) | |
| download | op-kernel-dev-dd7b2f035ec41a409f7a7cec7aabc0ec0eacf476.zip op-kernel-dev-dd7b2f035ec41a409f7a7cec7aabc0ec0eacf476.tar.gz | |
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 <benh@kernel.crashing.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Change log verbosification]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/hash64_4k.c')
| -rw-r--r-- | arch/powerpc/mm/hash64_4k.c | 2 |
1 files changed, 1 insertions, 1 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); |
