# git rev-parse -q --verify 44960f2a7b63e224b1091b3e1d6f60e0cdf4be0c^{commit} 44960f2a7b63e224b1091b3e1d6f60e0cdf4be0c already have revision, skipping fetch # git checkout -q -f -B kisskb 44960f2a7b63e224b1091b3e1d6f60e0cdf4be0c # git clean -qxdf # < git log -1 # commit 44960f2a7b63e224b1091b3e1d6f60e0cdf4be0c # Author: John Stultz # Date: Tue Jul 31 10:17:04 2018 -0700 # # staging: ashmem: Fix SIGBUS crash when traversing mmaped ashmem pages # # Amit Pundir and Youling in parallel reported crashes with recent # mainline kernels running Android: # # F DEBUG : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** # F DEBUG : Build fingerprint: 'Android/db410c32_only/db410c32_only:Q/OC-MR1/102:userdebug/test-key # F DEBUG : Revision: '0' # F DEBUG : ABI: 'arm' # F DEBUG : pid: 2261, tid: 2261, name: zygote >>> zygote <<< # F DEBUG : signal 7 (SIGBUS), code 2 (BUS_ADRERR), fault addr 0xec00008 # ... ... # F DEBUG : backtrace: # F DEBUG : #00 pc 00001c04 /system/lib/libc.so (memset+48) # F DEBUG : #01 pc 0010c513 /system/lib/libart.so (create_mspace_with_base+82) # F DEBUG : #02 pc 0015c601 /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateMspace(void*, unsigned int, unsigned int)+40) # F DEBUG : #03 pc 0015c3ed /system/lib/libart.so (art::gc::space::DlMallocSpace::CreateFromMemMap(art::MemMap*, std::__1::basic_string, std::__1::allocator> const&, unsigned int, unsigned int, unsigned int, unsigned int, bool)+36) # ... # # This was bisected back to commit bfd40eaff5ab ("mm: fix # vma_is_anonymous() false-positives"). # # create_mspace_with_base() in the trace above, utilizes ashmem, and with # ashmem, for shared mappings we use shmem_zero_setup(), which sets the # vma->vm_ops to &shmem_vm_ops. But for private ashmem mappings nothing # sets the vma->vm_ops. # # Looking at the problematic patch, it seems to add a requirement that one # call vma_set_anonymous() on a vma, otherwise the dummy_vm_ops will be # used. Using the dummy_vm_ops seem to triggger SIGBUS when traversing # unmapped pages. # # Thus, this patch adds a call to vma_set_anonymous() for ashmem private # mappings and seems to avoid the reported problem. # # Fixes: bfd40eaff5ab ("mm: fix vma_is_anonymous() false-positives") # Cc: Kirill Shutemov # Cc: Andrew Morton # Cc: Dmitry Vyukov # Cc: Oleg Nesterov # Cc: Andrea Arcangeli # Cc: Greg Kroah-Hartman # Cc: Hugh Dickins # Cc: Joel Fernandes # Cc: Colin Cross # Cc: Matthew Wilcox # Reported-by: Amit Pundir # Reported-by: Youling 257 # Signed-off-by: John Stultz # Signed-off-by: Linus Torvalds # < /opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux-gcc --version # < git log --format=%s --max-count=1 44960f2a7b63e224b1091b3e1d6f60e0cdf4be0c # < make -s -j 10 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- randconfig KCONFIG_SEED=0x6EA4BC84 # 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 # yes \n | make -s -j 10 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_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 10 ARCH=powerpc O=/kisskb/build/linus-rand_powerpc-randconfig_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- /kisskb/src/ipc/shm.c: In function 'ksys_shmdt': /kisskb/src/ipc/shm.c:1648:59: warning: 'file' 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/mm/memory.c:84:2: warning: #warning Unfortunate NUMA and NUMA Balancing config, growing page-frame for last_cpupid. [-Wcpp] /kisskb/src/sound/hda/hdac_regmap.c: In function 'hda_reg_write': /kisskb/src/sound/hda/hdac_regmap.c:282:16: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/mpi/mpicoder.c: In function 'mpi_read_raw_from_sgl': /kisskb/src/lib/mpi/mpicoder.c:352:8: warning: 'buff' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/char/tpm/tpm-sysfs.c: In function 'pubek_show': /kisskb/src/drivers/char/tpm/tpm-sysfs.c:37:16: warning: 'tpm_buf.data' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/dma-buf/reservation.c: In function 'reservation_object_add_shared_replace': /kisskb/src/drivers/dma-buf/reservation.c:210:7: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/lib/rhashtable.c: In function 'rhashtable_rehash_one': /kisskb/src/lib/rhashtable.c:269:2: warning: 'next' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/core/gen_stats.c: In function '__gnet_stats_copy_basic': /kisskb/src/net/core/gen_stats.c:161:19: warning: 'seq' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/sound/soc/codecs/da7219-aad.c: In function 'da7219_aad_hptest_work': /kisskb/src/sound/soc/codecs/da7219-aad.c:318:17: warning: 'pll_ctrl' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/core/flow_dissector.c: In function '__skb_flow_dissect': /kisskb/src/net/core/flow_dissector.c:789:7: warning: 'vlan' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/core/dev.c: In function 'validate_xmit_skb_list': /kisskb/src/net/core/dev.c:3161:15: warning: 'tail' 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/drivers/slimbus/messaging.c: In function 'slim_do_transfer': /kisskb/src/drivers/slimbus/messaging.c:126:14: warning: 'tid' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/scsi/aacraid/src.c: In function 'aac_src_intr_message': /kisskb/src/drivers/scsi/aacraid/src.c:98:4: warning: 'bellbits' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c: In function 'ibmvscsis_rdma': /kisskb/src/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:3323:18: warning: 'server_ioba' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c:3317:18: warning: 'client_ioba' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c: In function 'serial_unlink_irq_chain': /kisskb/src/drivers/tty/serial/8250/8250_core.c:246:2: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/target/target_core_user.c: In function 'scatter_data_area': /kisskb/src/drivers/target/target_core_user.c:573:29: warning: 'dbi' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/target/target_core_user.c:587:9: note: 'dbi' was declared here /kisskb/src/drivers/scsi/am53c974.c: In function 'pci_esp_dma_drain': /kisskb/src/drivers/scsi/am53c974.c:199:6: warning: 'resid' may be used uninitialized in this function [-Wuninitialized] Completed OK # rm -rf /kisskb/build/linus-rand_powerpc-randconfig_powerpc # Build took: 0:03:34.903927