Le 02/06/2020 à 00:58, Andrew Doran a écrit :
Module Name: src Committed By: ad Date: Mon Jun 1 22:58:06 UTC 2020Modified Files: src/sys/arch/amd64/amd64: cpufunc.S src/sys/arch/amd64/include: frameasm.h Log Message: Reported-by: syzbot+6dd5a230d19f0cbc7...@syzkaller.appspotmail.com Instrument STOS/MOVS for KMSAN to unbreak it. To generate a diff of this commit: cvs rdiff -u -r1.58 -r1.59 src/sys/arch/amd64/amd64/cpufunc.S cvs rdiff -u -r1.49 -r1.50 src/sys/arch/amd64/include/frameasm.h Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files.
Can you just stop ignoring the remarks that are made? I said explicitly that adding manual instrumentation here is _wrong_. The kMSan ASM fixups are limited to args/returns, and that is part of a sensical policy that _should not_ be changed without a good reason. x86_movs/x86_stos have strictly _no reason_ to exist. Of the 18 conversions you made to them in pmap.c, not one is justified. memcpy/memset were all correct. The only reason you made these big unneeded changes is for SVS not to take the bus lock, but as was said already, atomic_load_relaxed will do what you want without the need for these functions. Please revert _both changes now_, this one and the previous one which introduced both functions, and let's use atomic_load_relaxed. Maxime
