From: Ben Hutchings Date: Tue, 9 May 2017 17:00:43 +0000 (+0100) Subject: x86, pmem: Fix cache flushing for iovec write < 8 bytes X-Git-Tag: release-20171130_firefly~4^2~100^2~1^2~8^2~36 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b8cd9dd513bf944f5070203f3c0063d9796e4221;p=firefly-linux-kernel-4.4.55.git x86, pmem: Fix cache flushing for iovec write < 8 bytes commit 8376efd31d3d7c44bd05be337adde023cc531fa1 upstream. Commit 11e63f6d920d added cache flushing for unaligned writes from an iovec, covering the first and last cache line of a >= 8 byte write and the first cache line of a < 8 byte write. But an unaligned write of 2-7 bytes can still cover two cache lines, so make sure we flush both in that case. Fixes: 11e63f6d920d ("x86, pmem: fix broken __copy_user_nocache ...") Signed-off-by: Ben Hutchings Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/include/asm/pmem.h b/arch/x86/include/asm/pmem.h index bd8ce6bcdfc9..6503526d7b24 100644 --- a/arch/x86/include/asm/pmem.h +++ b/arch/x86/include/asm/pmem.h @@ -122,7 +122,7 @@ static inline size_t arch_copy_from_iter_pmem(void __pmem *addr, size_t bytes, if (bytes < 8) { if (!IS_ALIGNED(dest, 4) || (bytes != 4)) - __arch_wb_cache_pmem(addr, 1); + __arch_wb_cache_pmem(addr, bytes); } else { if (!IS_ALIGNED(dest, 8)) { dest = ALIGN(dest, boot_cpu_data.x86_clflush_size);