# git rev-parse -q --verify 8077155dce6c20909682788466ddb25af743cb73^{commit} 8077155dce6c20909682788466ddb25af743cb73 already have revision, skipping fetch # git checkout -q -f -B kisskb 8077155dce6c20909682788466ddb25af743cb73 # git clean -qxdf # < git log -1 # commit 8077155dce6c20909682788466ddb25af743cb73 # Author: Nicholas Piggin # Date: Fri Nov 20 12:57:57 2020 +1000 # # powerpc/64s: Trim offlined CPUs from mm_cpumasks # # When offlining a CPU, powerpc/64s does not flush TLBs, rather it just # leaves the CPU set in mm_cpumasks, so it continues to receive TLBIEs # to manage its TLBs. # # However the exit_flush_lazy_tlbs() function expects that after # returning, all CPUs (except self) have flushed TLBs for that mm, in # which case TLBIEL can be used for this flush. This breaks for offline # CPUs because they don't get the IPI to flush their TLB. This can lead # to stale translations. # # Fix this by clearing the CPU from mm_cpumasks, then flushing all TLBs # before going offline. # # These offlined CPU bits stuck in the cpumask also prevents the cpumask # from being trimmed back to local mode, which means continual broadcast # IPIs or TLBIEs are needed for TLB flushing. This patch prevents that # situation too. # # Signed-off-by: Nicholas Piggin # Signed-off-by: Michael Ellerman # Link: https://lore.kernel.org/r/20201120025757.325930-3-npiggin@gmail.com # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 8077155dce6c20909682788466ddb25af743cb73 # < make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_corenet32_smp_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- corenet32_smp_defconfig # make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_corenet32_smp_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- INFO: Uncompressed kernel (size 0xe514b4) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xf00000) Image Name: Linux-5.10.0-rc2-g8077155dce6c Created: Sat Nov 21 03:06:30 2020 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 6740622 Bytes = 6582.64 KiB = 6.43 MiB Load Address: 00000000 Entry Point: 00000000 Completed OK # rm -rf /kisskb/build/powerpc-fixes_corenet32_smp_defconfig_powerpc-gcc4.9 # Build took: 0:01:21.806887