# git rev-parse -q --verify b03897cf318dfc47de33a7ecbc7655584266f034^{commit} b03897cf318dfc47de33a7ecbc7655584266f034 already have revision, skipping fetch # git checkout -q -f -B kisskb b03897cf318dfc47de33a7ecbc7655584266f034 # git clean -qxdf # < git log -1 # commit b03897cf318dfc47de33a7ecbc7655584266f034 # Author: Gautham R. Shenoy # Date: Wed Jul 18 14:03:16 2018 +0530 # # powerpc/powernv: Fix save/restore of 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 (Power9 only) and above. # # Thus in this situation, on POWER9, 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 restoring SPRN_SPRG3 on wake up from a deep stop state # with the sprg_vdso value that is cached in PACA. # # 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 # Reviewed-by: Michael Ellerman # 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 b03897cf318dfc47de33a7ecbc7655584266f034 # < make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_44x_bamboo_defconfig_powerpc-5.3 CROSS_COMPILE=/opt/cross/kisskb/gcc-5.3.0-nolibc/powerpc64-linux/bin/powerpc64-linux- 44x/bamboo_defconfig # make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-fixes_44x_bamboo_defconfig_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. INFO: Uncompressed kernel (size 0x42f650) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0x500000) INFO: Uncompressed kernel (size 0x42f650) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0x500000) Image Name: Linux-4.18.0-rc3-gb03897c Created: Thu Jul 19 02:45:43 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 2141303 Bytes = 2091.12 kB = 2.04 MB Load Address: 00500000 Entry Point: 0050018c Completed OK # rm -rf /kisskb/build/powerpc-fixes_44x_bamboo_defconfig_powerpc-5.3 # Build took: 0:00:17.671979