# git rev-parse -q --verify 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479^{commit} 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 already have revision, skipping fetch # git checkout -q -f -B kisskb 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 # git clean -qxdf # < git log -1 # commit 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 # Author: Suraj Jitindar Singh # Date: Thu Jun 20 11:46:51 2019 +1000 # # KVM: PPC: Book3S HV: Clear pending decrementer exceptions on nested guest entry # # If we enter an L1 guest with a pending decrementer exception then this # is cleared on guest exit if the guest has writtien a positive value # into the decrementer (indicating that it handled the decrementer # exception) since there is no other way to detect that the guest has # handled the pending exception and that it should be dequeued. In the # event that the L1 guest tries to run a nested (L2) guest immediately # after this and the L2 guest decrementer is negative (which is loaded # by L1 before making the H_ENTER_NESTED hcall), then the pending # decrementer exception isn't cleared and the L2 entry is blocked since # L1 has a pending exception, even though L1 may have already handled # the exception and written a positive value for it's decrementer. This # results in a loop of L1 trying to enter the L2 guest and L0 blocking # the entry since L1 has an interrupt pending with the outcome being # that L2 never gets to run and hangs. # # Fix this by clearing any pending decrementer exceptions when L1 makes # the H_ENTER_NESTED hcall since it won't do this if it's decrementer # has gone negative, and anyway it's decrementer has been communicated # to L0 in the hdec_expires field and L0 will return control to L1 when # this goes negative by delivering an H_DECREMENTER exception. # # Fixes: 95a6432ce903 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests") # Cc: stable@vger.kernel.org # v4.20+ # Signed-off-by: Suraj Jitindar Singh # Signed-off-by: Michael Ellerman # < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-gcc --version # < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-ld --version # < git log --format=%s --max-count=1 3c25ab35fbc8526ac0c9b298e8a78e7ad7a55479 # < make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-next-rand_powerpc-randconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- randconfig KCONFIG_SEED=0x30425A18 # Added to kconfig CONFIG_STANDALONE=y # Added to kconfig CONFIG_BUILD_DOCSRC=n # Added to kconfig CONFIG_MODULE_SIG=n # Added to kconfig CONFIG_CPU_BIG_ENDIAN=y # Added to kconfig CONFIG_PPC64=y # Added to kconfig CONFIG_PPC_DISABLE_WERROR=y # Added to kconfig CONFIG_SECTION_MISMATCH_WARN_ONLY=y # Added to kconfig CONFIG_PREVENT_FIRMWARE_BUILD=y # Added to kconfig CONFIG_CC_STACKPROTECTOR_STRONG=n # Added to kconfig CONFIG_GCC_PLUGINS=n # Added to kconfig CONFIG_LD_HEAD_STUB_CATCH=y # Added to kconfig CONFIG_TRIM_UNUSED_KSYMS=n # Added to kconfig CONFIG_UBSAN=n # yes \n | make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-next-rand_powerpc-randconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- oldconfig yes: standard output: Broken pipe # make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-next-rand_powerpc-randconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- /kisskb/src/kernel/printk/printk.c: In function 'devkmsg_sysctl_set_loglvl': /kisskb/src/kernel/printk/printk.c:194:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/f2fs/file.c: In function 'f2fs_precache_extents': /kisskb/src/fs/f2fs/file.c:2951:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/f2fs/node.c: In function '__set_nat_cache_dirty': /kisskb/src/include/linux/list.h:93:12: warning: 'head' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/f2fs/node.c:237:24: note: 'head' was declared here /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:331:21: note: 'pdeo' was declared here /kisskb/src/fs/f2fs/segment.c: In function 'f2fs_flush_sit_entries': /kisskb/src/fs/f2fs/segment.c:3832:5: warning: array subscript is below array bounds [-Warray-bounds] /kisskb/src/fs/btrfs/ref-verify.c: In function 'btrfs_build_ref_tree': /kisskb/src/fs/btrfs/ref-verify.c:582:7: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/btrfs/ref-verify.c:503:35: note: 'ret' was declared here /kisskb/src/fs/btrfs/ref-verify.c:542:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/fs/btrfs/ref-verify.c:439:12: note: 'ret' was declared here /kisskb/src/drivers/base/regmap/regmap.c: In function 'regmap_raw_read': /kisskb/src/drivers/base/regmap/regmap.c:2589:6: 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:1850:6: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c: In function 'amdgpu_set_pp_od_clk_voltage': /kisskb/src/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c:685:6: warning: 'ret' 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:247:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c:227:19: note: 'i' was declared here /kisskb/src/drivers/usb/misc/usbtest.c: In function 'test_queue': /kisskb/src/drivers/usb/misc/usbtest.c:2148:1: warning: the frame size of 1184 bytes is larger than 1024 bytes [-Wframe-larger-than=] /kisskb/src/lib/string.c: In function 'strim': /kisskb/src/lib/string.c:512:8: sorry, unimplemented: inlining failed in call to 'strlen': redefined extern inline functions are not considered for inlining /kisskb/src/lib/string.c:494:7: sorry, unimplemented: called from here make[2]: *** [/kisskb/src/scripts/Makefile.build:278: lib/string.o] Error 1 make[2]: *** Waiting for unfinished jobs.... make[1]: *** [/kisskb/src/Makefile:1071: lib] Error 2 make[1]: *** Waiting for unfinished jobs.... /kisskb/src/drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.c: In function 'gk104_top_oneinit': /kisskb/src/drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.c:104:1: warning: 'inst' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.c:104:1: warning: 'type' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dce_calcs.c: In function 'bw_calcs_init': /kisskb/src/drivers/gpu/drm/amd/amdgpu/../display/dc/calcs/dce_calcs.c:2731:1: warning: the frame size of 1088 bytes is larger than 1024 bytes [-Wframe-larger-than=] make: *** [Makefile:179: sub-make] Error 2 Command 'make -s -j 120 ARCH=powerpc O=/kisskb/build/powerpc-next-rand_powerpc-randconfig_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- ' returned non-zero exit status 2 # rm -rf /kisskb/build/powerpc-next-rand_powerpc-randconfig_powerpc-gcc4.6 # Build took: 0:01:31.877151