# git rev-parse -q --verify 0fc810ae3ae110f9e2fcccce80fc8c8d62f97907^{commit} 0fc810ae3ae110f9e2fcccce80fc8c8d62f97907 already have revision, skipping fetch # git checkout -q -f -B kisskb 0fc810ae3ae110f9e2fcccce80fc8c8d62f97907 # git clean -qxdf # < git log -1 # commit 0fc810ae3ae110f9e2fcccce80fc8c8d62f97907 # Author: Linus Torvalds # Date: Tue Oct 29 16:03:31 2024 -1000 # # x86/uaccess: Avoid barrier_nospec() in 64-bit copy_from_user() # # The barrier_nospec() in 64-bit copy_from_user() is slow. Instead use # pointer masking to force the user pointer to all 1's for an invalid # address. # # The kernel test robot reports a 2.6% improvement in the per_thread_ops # benchmark [1]. # # This is a variation on a patch originally by Josh Poimboeuf [2]. # # Link: https://lore.kernel.org/202410281344.d02c72a2-oliver.sang@intel.com [1] # Link: https://lore.kernel.org/5b887fe4c580214900e21f6c61095adf9a142735.1730166635.git.jpoimboe@kernel.org [2] # Tested-and-reviewed-by: Josh Poimboeuf # Cc: Kirill A. Shutemov # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/x86-64--glibc--bleeding-edge-2022.08-1/bin/x86_64-linux-gcc --version # < /opt/cross/kisskb/x86-64--glibc--bleeding-edge-2022.08-1/bin/x86_64-linux-ld --version # < git log --format=%s --max-count=1 0fc810ae3ae110f9e2fcccce80fc8c8d62f97907 # make -s -j 40 ARCH=um O=/kisskb/build/linus_defconfig_um-x86_64-gcc12 CROSS_COMPILE=/opt/cross/kisskb/x86-64--glibc--bleeding-edge-2022.08-1/bin/x86_64-linux- SUBARCH=x86_64 defconfig # < make -s -j 40 ARCH=um O=/kisskb/build/linus_defconfig_um-x86_64-gcc12 CROSS_COMPILE=/opt/cross/kisskb/x86-64--glibc--bleeding-edge-2022.08-1/bin/x86_64-linux- SUBARCH=x86_64 help # make -s -j 40 ARCH=um O=/kisskb/build/linus_defconfig_um-x86_64-gcc12 CROSS_COMPILE=/opt/cross/kisskb/x86-64--glibc--bleeding-edge-2022.08-1/bin/x86_64-linux- SUBARCH=x86_64 olddefconfig # make -s -j 40 ARCH=um O=/kisskb/build/linus_defconfig_um-x86_64-gcc12 CROSS_COMPILE=/opt/cross/kisskb/x86-64--glibc--bleeding-edge-2022.08-1/bin/x86_64-linux- SUBARCH=x86_64 LINK linux Completed OK # rm -rf /kisskb/build/linus_defconfig_um-x86_64-gcc12 # Build took: 0:00:35.893013