# git rev-parse -q --verify a75a001540d03c30315e43884ad95cc68040f18d^{commit} a75a001540d03c30315e43884ad95cc68040f18d already have revision, skipping fetch # git checkout -q -f -B kisskb a75a001540d03c30315e43884ad95cc68040f18d # git clean -qxdf # < git log -1 # commit a75a001540d03c30315e43884ad95cc68040f18d # Author: Michael Ellerman # Date: Thu Nov 1 16:21:05 2018 +1100 # # powerpc/mm/64s: Fix preempt warning in slb_allocate_kernel() # # With preempt enabled we see warnings in do_slb_fault(): # # BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u33:0/98 # futex hash table entries: 4096 (order: 3, 524288 bytes) # caller is do_slb_fault+0x204/0x230 # CPU: 5 PID: 98 Comm: kworker/u33:0 Not tainted 4.19.0-rc3-gcc-7.3.1-00022-g1936f094e164 #138 # Call Trace: # dump_stack+0xb4/0x104 (unreliable) # check_preemption_disabled+0x148/0x150 # do_slb_fault+0x204/0x230 # data_access_slb_common+0x138/0x180 # # This is caused by the get_paca() in slb_allocate_kernel(), which # includes a call to debug_smp_processor_id(). # # slb_allocate_kernel() can only be called from do_slb_fault(), and in # that path interrupts are hard disabled and so we can't be preempted, # but we can't update the preempt flags (in thread_info) because that # could cause an SLB fault. # # So just use local_paca which is safe and doesn't cause the warning. # # Fixes: 48e7b7695745 ("powerpc/64s/hash: Convert SLB miss handlers to C") # 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 a75a001540d03c30315e43884ad95cc68040f18d # < make -s -j 8 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+NO_MEMORY_HOTREMOVE_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- pseries_defconfig # Added to kconfig CONFIG_MEMORY_HOTPLUG=y # Added to kconfig CONFIG_MEMORY_HOTREMOVE=n # yes \n | make -s -j 8 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+NO_MEMORY_HOTREMOVE_powerpc CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- oldconfig yes: standard output: Broken pipe # make -s -j 8 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+NO_MEMORY_HOTREMOVE_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: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:186:16: warning: 'old' 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/drivers/base/regmap/regmap.c: In function 'regmap_raw_read': /kisskb/src/drivers/base/regmap/regmap.c:2594:6: 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:1855:6: warning: 'ret' 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:2076:9: warning: 'str' 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:341:21: note: 'pdeo' was declared here /kisskb/src/net/bridge/br_netlink.c: In function 'br_afspec': /kisskb/src/net/bridge/br_netlink.c:647:7: warning: 'err' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/i2c/i2c-core-base.c: In function 'i2c_generic_scl_recovery': /kisskb/src/drivers/i2c/i2c-core-base.c:235:5: warning: 'ret' may be used uninitialized in this function [-Wuninitialized] /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/drivers/net/tun.c: In function 'tun_get_user': /kisskb/src/drivers/net/tun.c:1819:30: warning: 'copylen' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c:1729:46: warning: 'linear' 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 Completed OK # rm -rf /kisskb/build/powerpc-fixes_pseries_defconfig+NO_MEMORY_HOTREMOVE_powerpc # Build took: 0:04:13.762160