Re: [PATCH v3 1/5] powerpc: Allow flush_icache_range to work across ranges >4GB
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2019-09-19 03:43:52
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lkml, stable
"Alastair D'Silva" [off-list ref] writes:
From: Alastair D'Silva <redacted> When calling flush_icache_range with a size >4GB, we were masking off the upper 32 bits, so we would incorrectly flush a range smaller than intended. __kernel_sync_dicache in the 64 bit VDSO has the same bug.
Please fix that in a separate patch. Your subject doesn't mention __kernel_sync_dicache(), and also the two changes backport differently, so it's better if they're done as separate patches. cheers
quoted hunk ↗ jump to hunk
This patch replaces the 32 bit shifts with 64 bit ones, so that the full size is accounted for. Signed-off-by: Alastair D'Silva <redacted> Cc: stable@vger.kernel.org --- arch/powerpc/kernel/misc_64.S | 4 ++-- arch/powerpc/kernel/vdso64/cacheflush.S | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-)diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index b55a7b4cb543..9bc0aa9aeb65 100644 --- a/arch/powerpc/kernel/misc_64.S +++ b/arch/powerpc/kernel/misc_64.S@@ -82,7 +82,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE) subf r8,r6,r4 /* compute length */ add r8,r8,r5 /* ensure we get enough */ lwz r9,DCACHEL1LOGBLOCKSIZE(r10) /* Get log-2 of cache block size */ - srw. r8,r8,r9 /* compute line count */ + srd. r8,r8,r9 /* compute line count */ beqlr /* nothing to do? */ mtctr r8 1: dcbst 0,r6@@ -98,7 +98,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE) subf r8,r6,r4 /* compute length */ add r8,r8,r5 lwz r9,ICACHEL1LOGBLOCKSIZE(r10) /* Get log-2 of Icache block size */ - srw. r8,r8,r9 /* compute line count */ + srd. r8,r8,r9 /* compute line count */ beqlr /* nothing to do? */ mtctr r8 2: icbi 0,r6diff --git a/arch/powerpc/kernel/vdso64/cacheflush.S b/arch/powerpc/kernel/vdso64/cacheflush.S index 3f92561a64c4..526f5ba2593e 100644 --- a/arch/powerpc/kernel/vdso64/cacheflush.S +++ b/arch/powerpc/kernel/vdso64/cacheflush.S@@ -35,7 +35,7 @@ V_FUNCTION_BEGIN(__kernel_sync_dicache) subf r8,r6,r4 /* compute length */ add r8,r8,r5 /* ensure we get enough */ lwz r9,CFG_DCACHE_LOGBLOCKSZ(r10) - srw. r8,r8,r9 /* compute line count */ + srd. r8,r8,r9 /* compute line count */ crclr cr0*4+so beqlr /* nothing to do? */ mtctr r8@@ -52,7 +52,7 @@ V_FUNCTION_BEGIN(__kernel_sync_dicache) subf r8,r6,r4 /* compute length */ add r8,r8,r5 lwz r9,CFG_ICACHE_LOGBLOCKSZ(r10) - srw. r8,r8,r9 /* compute line count */ + srd. r8,r8,r9 /* compute line count */ crclr cr0*4+so beqlr /* nothing to do? */ mtctr r8-- 2.21.0