Hi Jian, On Thu, Oct 29, 2020 at 06:13:07PM -0700, 'Jian Cai' via Clang Built Linux wrote: > Thanks @Nick Desaulniers <ndesaulniers@xxxxxxxxxx> and @Sasha Levin > <sashal@xxxxxxxxxx> for the tips. For this particular change, it seems we > do not need to backport all the dependencies (if they have not been merged > into 5.4 stable). @Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>, please find the > custom backport as below. It has passed all the tests on ChromeOS ( > http://crrev.com/c/2504570). > > Thanks, > Jian The below patch won't apply because it appears to be copy pasted into this message: Applying: Backport 44623b2818f4a442726639572f44fd9b6d0ef68c to kernel 5.4 error: git diff header lacks filename information when removing 1 leading pathname component (line 6) Patch failed at 0001 Backport 44623b2818f4a442726639572f44fd9b6d0ef68c to kernel 5.4 hint: Use 'git am --show-current-patch=diff' to see the failed patch When you have resolved this problem, run "git am --continue". If you prefer to skip this patch, run "git am --skip" instead. To restore the original branch and stop patching, run "git am --abort". I would recommend resending the patch with git send-email or attaching the patch file created by 'git format-patch -1' to a future email for proper application. > From 60891062750a39d8bba9710d500e381a26c11f75 Mon Sep 17 00:00:00 2001 > From: Jian Cai <jiancai@xxxxxxxxxx> > Date: Thu, 29 Oct 2020 17:49:39 -0700 Authorship and date should be fixed to retain the information of the original commit. It is trivial to just redo the cherry-pick to fix that information in this instance but this is the command I usually run for more non-trivial backports that I have already done: $ git commit -s --amend -C <sha> --date "$(git show -s --format=%ai <sha>)" This should allow you to retain the commit message of the original message along with the author's date. > Subject: [PATCH] crypto: x86/crc32c - fix building with clang ias > > commit 44623b2818f4a442726639572f44fd9b6d0ef68c upstream > > The clang integrated assembler complains about movzxw: > > arch/x86/crypto/crc32c-pcl-intel-asm_64.S:173:2: error: invalid instruction > mnemonic 'movzxw' > > It seems that movzwq is the mnemonic that it expects instead, > and this is what objdump prints when disassembling the file. > > NOTE: this is a custom backport as the surrounding code has been > changed upstream. A note of this nature is traditionally placed after the signoffs of the original patch like my example below: > Fixes: 6a8ce1ef3940 ("crypto: crc32c - Optimize CRC32C calculation with > PCLMULQDQ instruction") > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> > Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> [jc: Backport to 5.4] > Signed-off-by: Jian Cai <caij2003@xxxxxxxxx> I usually like to notate why the patch did not apply cleanly so that it is easier for others to audit, such as: [jc: Fixed conflicts due to lack of 34fdce6981b969] That is merely a suggestion, not required by any means. Otherwise, the backport seems obvious fine to me. Cheers, Nathan > --- > arch/x86/crypto/crc32c-pcl-intel-asm_64.S | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/crypto/crc32c-pcl-intel-asm_64.S > b/arch/x86/crypto/crc32c-pcl-intel-asm_64.S > index d9b734d0c8cc..3c6e01520a97 100644 > --- a/arch/x86/crypto/crc32c-pcl-intel-asm_64.S > +++ b/arch/x86/crypto/crc32c-pcl-intel-asm_64.S > @@ -170,7 +170,7 @@ continue_block: > > ## branch into array > lea jump_table(%rip), bufp > - movzxw (bufp, %rax, 2), len > + movzwq (bufp, %rax, 2), len > lea crc_array(%rip), bufp > lea (bufp, len, 1), bufp > JMP_NOSPEC bufp > -- > 2.29.1.341.ge80a0c044ae-goog
