This is a note to let you know that I've just added the patch titled x86, pmem: Fix cache flushing for iovec write < 8 bytes to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-pmem-fix-cache-flushing-for-iovec-write-8-bytes.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 8376efd31d3d7c44bd05be337adde023cc531fa1 Mon Sep 17 00:00:00 2001 From: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx> Date: Tue, 9 May 2017 18:00:43 +0100 Subject: x86, pmem: Fix cache flushing for iovec write < 8 bytes From: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx> 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 <ben.hutchings@xxxxxxxxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/include/asm/pmem.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/include/asm/pmem.h +++ b/arch/x86/include/asm/pmem.h @@ -103,7 +103,7 @@ static inline size_t arch_copy_from_iter 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); Patches currently in stable-queue which might be from ben.hutchings@xxxxxxxxxxxxxxx are queue-4.11/x86-pmem-fix-cache-flushing-for-iovec-write-8-bytes.patch