# 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-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-gcc --version # < git log --format=%s --max-count=1 b03897cf318dfc47de33a7ecbc7655584266f034 # < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+FA_DUMP_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- pseries_defconfig # Added to kconfig CONFIG_CRASH_DUMP=y # Added to kconfig CONFIG_FA_DUMP=y # yes \n | make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+FA_DUMP_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- oldconfig yes: standard output: Broken pipe yes: write error # make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+FA_DUMP_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- /kisskb/src/net/Makefile:24: CC cannot link executables. Skipping bpfilter. /kisskb/src/net/Makefile:24: CC cannot link executables. Skipping bpfilter. /kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount': /kisskb/src/kernel/cgroup/cgroup-v1.c:1256:20: warning: 'root' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl': /kisskb/src/kernel/printk/printk.c:183:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read': /kisskb/src/drivers/base/regmap/regmap.c:2497:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/base/regmap/regmap.c: In function '_regmap_raw_write': /kisskb/src/drivers/base/regmap/regmap.c:1819:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/bridge/br_netlink.c: In function 'br_afspec': /kisskb/src/net/bridge/br_netlink.c:637:7: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/mm/swap_state.c: In function '__add_to_swap_cache': /kisskb/src/mm/swap_state.c:135:5: warning: 'error' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/mm/hugetlb.c: In function 'alloc_pool_huge_page': /kisskb/src/mm/hugetlb.c:1433:5: warning: 'page' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/proc/inode.c: In function 'proc_reg_open': /kisskb/src/include/linux/list.h:65:12: warning: 'pdeo' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/proc/inode.c:339:21: note: 'pdeo' was declared here /kisskb/src/fs/udf/unicode.c: In function 'udf_name_conv_char': /kisskb/src/fs/udf/unicode.c:132:8: warning: 'c' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/nfsd/nfs4xdr.c: In function 'nfsd4_encode_components_esc': /kisskb/src/fs/nfsd/nfs4xdr.c:2046:9: warning: 'str' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq': /kisskb/src/drivers/tty/serial/8250/8250_core.c:251:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c:231:19: note: 'i' was declared here /kisskb/src/drivers/net/tun.c: In function 'tun_get_user': /kisskb/src/drivers/net/tun.c:1835:30: warning: 'copylen' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c:1745:46: warning: 'linear' may be used uninitialized in this function [-Wuninitialized] Completed OK # rm -rf /kisskb/build/powerpc-fixes_pseries_defconfig+FA_DUMP_powerpc # Build took: 0:02:16.952494