# git rev-parse -q --verify 34f0ee3c18c1ba6b31eea86c1e154ef1a7f31d56^{commit} 34f0ee3c18c1ba6b31eea86c1e154ef1a7f31d56 already have revision, skipping fetch # git checkout -q -f -B kisskb 34f0ee3c18c1ba6b31eea86c1e154ef1a7f31d56 # git clean -qxdf # < git log -1 # commit 34f0ee3c18c1ba6b31eea86c1e154ef1a7f31d56 # Author: Gautham R. Shenoy # Date: Tue Jul 17 16:57:29 2018 +0530 # # powerpc/powernv: Save & Restore SPRG3 on entry/exit from stop (idle) # # On 64-bit Servers, SPRN_SPRG3 and its userspace read-only mirror # SPRN_USPRG3 are used as userspace VDSO write and read registers # respectively. # # SPRN_SPRG3 is lost when we enter stop4 and above, and is currently not # restored. As a result, any read from SPRN_USPRG3 returns zero on an # exit from stop4 and above. This affects Power9 only. # # Thus in this situation, any call from sched_getcpu() always returns # zero, as on powerpc, we call __kernel_getcpu() which relies upon # SPRN_USPRG3 to report the CPU and NUMA node information. # # Fix this by saving the SPRN_SPRG3 before entering a deep stop state, # and restoring it back on wakeup from the stop state. # # Fixes: e1c1cfed5432 ("powerpc/powernv: Save/Restore additional SPRs for stop4 cpuidle") # Cc: stable@vger.kernel.org # v4.14+ # Reported-by: Florian Weimer # Signed-off-by: Gautham R. Shenoy # Signed-off-by: Michael Ellerman # < /opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < git log --format=%s --max-count=1 34f0ee3c18c1ba6b31eea86c1e154ef1a7f31d56 # < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+POWERNV=n_powerpc-5.3 CROSS_COMPILE=/opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux- pseries_defconfig # Added to kconfig CONFIG_PPC_POWERNV=n # yes \n | make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+POWERNV=n_powerpc-5.3 CROSS_COMPILE=/opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux- oldconfig yes: standard output: Broken pipe yes: write error # make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+POWERNV=n_powerpc-5.3 CROSS_COMPILE=/opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux- /kisskb/src/net/Makefile:24: CC cannot link executables. Skipping bpfilter. /kisskb/src/net/Makefile:24: CC cannot link executables. Skipping bpfilter. Completed OK # rm -rf /kisskb/build/powerpc-fixes_pseries_defconfig+POWERNV=n_powerpc-5.3 # Build took: 0:02:34.879616