# git rev-parse -q --verify 56376c5864f8ff4ba7c78a80ae857eee3b1d23d8^{commit} 56376c5864f8ff4ba7c78a80ae857eee3b1d23d8 already have revision, skipping fetch # git checkout -q -f -B kisskb 56376c5864f8ff4ba7c78a80ae857eee3b1d23d8 # git clean -qxdf # < git log -1 # commit 56376c5864f8ff4ba7c78a80ae857eee3b1d23d8 # Author: Michael Ellerman # Date: Thu Apr 19 16:22:20 2018 +1000 # # powerpc/kvm: Fix lockups when running KVM guests on Power8 # # When running KVM guests on Power8 we can see a lockup where one CPU # stops responding. This often leads to a message such as: # # watchdog: CPU 136 detected hard LOCKUP on other CPUs 72 # Task dump for CPU 72: # qemu-system-ppc R running task 10560 20917 20908 0x00040004 # # And then backtraces on other CPUs, such as: # # Task dump for CPU 48: # ksmd R running task 10032 1519 2 0x00000804 # Call Trace: # ... # --- interrupt: 901 at smp_call_function_many+0x3c8/0x460 # LR = smp_call_function_many+0x37c/0x460 # pmdp_invalidate+0x100/0x1b0 # __split_huge_pmd+0x52c/0xdb0 # try_to_unmap_one+0x764/0x8b0 # rmap_walk_anon+0x15c/0x370 # try_to_unmap+0xb4/0x170 # split_huge_page_to_list+0x148/0xa30 # try_to_merge_one_page+0xc8/0x990 # try_to_merge_with_ksm_page+0x74/0xf0 # ksm_scan_thread+0x10ec/0x1ac0 # kthread+0x160/0x1a0 # ret_from_kernel_thread+0x5c/0x78 # # This is caused by commit 8c1c7fb0b5ec ("powerpc/64s/idle: avoid sync # for KVM state when waking from idle"), which added a check in # pnv_powersave_wakeup() to see if the kvm_hstate.hwthread_state is # already set to KVM_HWTHREAD_IN_KERNEL, and if so to skip the store and # test of kvm_hstate.hwthread_req. # # The problem is that the primary does not set KVM_HWTHREAD_IN_KVM when # entering the guest, so it can then come out to cede with # KVM_HWTHREAD_IN_KERNEL set. It can then go idle in kvm_do_nap after # setting hwthread_req to 1, but because hwthread_state is still # KVM_HWTHREAD_IN_KERNEL we will skip the test of hwthread_req when we # wake up from idle and won't go to kvm_start_guest. From there the # thread will return somewhere garbage and crash. # # Fix it by skipping the store of hwthread_state, but not the test of # hwthread_req, when coming out of idle. It's OK to skip the sync in # that case because hwthread_req will have been set on the same thread, # so there is no synchronisation required. # # Fixes: 8c1c7fb0b5ec ("powerpc/64s/idle: avoid sync for KVM state when waking from idle") # 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 56376c5864f8ff4ba7c78a80ae857eee3b1d23d8 # < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_mpc85xx_defconfig_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- mpc85xx_defconfig # make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_mpc85xx_defconfig_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- /kisskb/src/kernel/cgroup/cgroup-v1.c: In function 'cgroup1_mount': /kisskb/src/kernel/cgroup/cgroup-v1.c:1268:20: warning: 'root' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/soc/codecs/wm8960.c: In function 'wm8960_configure_clocking': /kisskb/src/sound/soc/codecs/wm8960.c:803:70: warning: 'j' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/soc/codecs/wm8960.c:800:68: warning: 'i' 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/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:340:21: note: 'pdeo' was declared here /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c: In function 'allocate_bd': /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c:139:6: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] /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 arch/powerpc/boot/mpc8541cds.dtb: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) arch/powerpc/boot/mpc8548cds_32b.dtb: Warning (pci_bridge): /pcie@e000a000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8548cds_32b.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge' arch/powerpc/boot/mpc8555cds.dtb: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) arch/powerpc/boot/mpc8572ds.dtb: Warning (pci_bridge): /pcie@ffe08000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8572ds.dtb: Warning (pci_bridge): /pcie@ffe09000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8572ds.dtb: Warning (pci_bridge): /pcie@ffe0a000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8572ds.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge' arch/powerpc/boot/tqm8548.dtb: Warning (pci_bridge): /pcie@e000a000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/tqm8548.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge' arch/powerpc/boot/sbc8548.dtb: Warning (pci_bridge): /pcie@e000a000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/sbc8548.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge' arch/powerpc/boot/mpc8568mds.dtb: Warning (pci_bridge): /pcie@e000a000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8568mds.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge' arch/powerpc/boot/mpc8544ds.dtb: Warning (pci_bridge): /pcie@e0009000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8544ds.dtb: Warning (pci_bridge): /pcie@e000a000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8544ds.dtb: Warning (pci_bridge): /pcie@e000b000/pcie@0: missing bus-range for PCI bridge arch/powerpc/boot/mpc8544ds.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge' INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb61400) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) INFO: Uncompressed kernel (size 0xb50cb4) overlaps the address of the wrapper(0x400000) INFO: Fixing the link_address of wrapper to (0xc00000) Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5480428 Bytes = 5351.98 kB = 5.23 MB Load Address: 00000000 Entry Point: 00000000 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5503848 Bytes = 5374.85 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504316 Bytes = 5375.31 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00288 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504020 Bytes = 5375.02 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00288 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504344 Bytes = 5375.34 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504697 Bytes = 5375.68 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504285 Bytes = 5375.28 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504072 Bytes = 5375.07 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00288 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:21 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504484 Bytes = 5375.47 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504288 Bytes = 5375.28 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504400 Bytes = 5375.39 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504073 Bytes = 5375.07 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00288 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504167 Bytes = 5375.16 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504370 Bytes = 5375.36 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00288 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504107 Bytes = 5375.10 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Image Name: Linux-4.17.0-rc1-g56376c5 Created: Thu Apr 19 20:24:22 2018 Image Type: PowerPC Linux Kernel Image (gzip compressed) Data Size: 5504460 Bytes = 5375.45 kB = 5.25 MB Load Address: 00c00000 Entry Point: 00c00248 Completed OK # rm -rf /kisskb/build/powerpc-fixes_mpc85xx_defconfig_powerpc # Build took: 0:01:29.829862