# git rev-parse -q --verify 9a48d604672220545d209e9996c2a1edbb5637f6^{commit} 9a48d604672220545d209e9996c2a1edbb5637f6 already have revision, skipping fetch # git checkout -q -f -B kisskb 9a48d604672220545d209e9996c2a1edbb5637f6 # git clean -qxdf # < git log -1 # commit 9a48d604672220545d209e9996c2a1edbb5637f6 # Author: Borislav Petkov (AMD) # Date: Fri May 12 23:12:26 2023 +0200 # # x86/retbleed: Fix return thunk alignment # # SYM_FUNC_START_LOCAL_NOALIGN() adds an endbr leading to this layout # (leaving only the last 2 bytes of the address): # # 3bff : # 3bff: f3 0f 1e fa endbr64 # 3c03: f6 test $0xcc,%bl # # 3c04 <__x86_return_thunk>: # 3c04: c3 ret # 3c05: cc int3 # 3c06: 0f ae e8 lfence # # However, "the RET at __x86_return_thunk must be on a 64 byte boundary, # for alignment within the BTB." # # Use SYM_START instead. # # Signed-off-by: Borislav Petkov (AMD) # Reviewed-by: Thomas Gleixner # Cc: # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux-ld --version # < git log --format=%s --max-count=1 9a48d604672220545d209e9996c2a1edbb5637f6 # < make -s -j 32 ARCH=x86_64 O=/kisskb/build/linus_x86_64-allnoconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- allnoconfig # < make -s -j 32 ARCH=x86_64 O=/kisskb/build/linus_x86_64-allnoconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- help # make -s -j 32 ARCH=x86_64 O=/kisskb/build/linus_x86_64-allnoconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- olddefconfig # make -s -j 32 ARCH=x86_64 O=/kisskb/build/linus_x86_64-allnoconfig_x86_64-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.5.0-nolibc/x86_64-linux/bin/x86_64-linux- Completed OK # rm -rf /kisskb/build/linus_x86_64-allnoconfig_x86_64-gcc8 # Build took: 0:00:27.538890