# git rev-parse -q --verify 892db32b07b340b60492e8e543aedc039639eef1^{commit} 892db32b07b340b60492e8e543aedc039639eef1 already have revision, skipping fetch # git checkout -q -f -B kisskb 892db32b07b340b60492e8e543aedc039639eef1 # git clean -qxdf # < git log -1 # commit 892db32b07b340b60492e8e543aedc039639eef1 # Author: David Hildenbrand # Date: Mon Dec 16 11:30:58 2019 +0100 # # powerpc/pseries/cmm: fix managed page counts when migrating pages between zones # # Commit 63341ab03706 (virtio-balloon: fix managed page counts when migrating # pages between zones) fixed a long existing BUG in the virtio-balloon # driver when pages would get migrated between zones. I did not try to # reproduce on powerpc, but looking at the code, the same should apply to # powerpc/cmm ever since it started using the balloon compaction # infrastructure (luckily just recently). # # In case we have to migrate a ballon page to a newpage of another zone, the # managed page count of both zones is wrong. Paired with memory offlining # (which will adjust the managed page count), we can trigger kernel crashes # and all kinds of different symptoms. # # Fix it by properly adjusting the managed page count when migrating if # the zone changed. # # We'll temporarily modify the totalram page count. If this ever becomes a # problem, we can fine tune by providing helpers that don't touch # the totalram pages (e.g., adjust_zone_managed_page_count()). # # Fixes: fe030c9b85e6 ("powerpc/pseries/cmm: Implement balloon compaction") # Signed-off-by: David Hildenbrand # Signed-off-by: Michael Ellerman # Link: https://lore.kernel.org/r/20191216103058.4958-1-david@redhat.com # < /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 892db32b07b340b60492e8e543aedc039639eef1 # < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+NO_SPLPAR_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- pseries_defconfig # Added to kconfig CONFIG_PPC_SPLPAR=n # yes \n | make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+NO_SPLPAR_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 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_pseries_defconfig+NO_SPLPAR_powerpc-gcc4.6 CROSS_COMPILE=/opt/cross/kisskb/gcc-4.6.3-nolibc/powerpc-linux/bin/powerpc-linux- /kisskb/src/fs/ext4/extents.c: In function 'ext4_convert_unwritten_io_end_vec': /kisskb/src/fs/ext4/extents.c:5054:23: warning: 'ret' 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:204:16: warning: 'old' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/net/bridge/br_netlink.c: In function 'br_afspec.isra.30': /kisskb/src/net/bridge/br_netlink.c:648:7: warning: 'err' 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:2591:6: 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:1852:6: warning: 'ret' 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:338:21: note: 'pdeo' was declared here /kisskb/src/mm/hugetlb.c: In function 'alloc_pool_huge_page': /kisskb/src/mm/hugetlb.c:1377:5: warning: 'page' 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/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/net/core/devlink.c: In function 'devlink_fmsg_prepare_skb': /kisskb/src/net/core/devlink.c:4613:6: warning: 'err' 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:248:18: warning: 'i' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/tty/serial/8250/8250_core.c:228:19: note: 'i' was declared here /kisskb/src/drivers/usb/core/devio.c: In function 'async_completed': /kisskb/src/drivers/usb/core/devio.c:625:23: warning: 'errno' 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:1836:30: warning: 'copylen' may be used uninitialized in this function [-Wuninitialized] /kisskb/src/drivers/net/tun.c:1749:46: warning: 'linear' may be used uninitialized in this function [-Wuninitialized] Completed OK # rm -rf /kisskb/build/powerpc-fixes_pseries_defconfig+NO_SPLPAR_powerpc-gcc4.6 # Build took: 0:02:17.455714