I regularly get kernel panics. Some of them are clearly related to btrfs, which is really unstable in software RAID1 configurations. But sometimes I get ones that appear unrelated, such as fairly regular panics related to rcu. A screen shot of the panic can be found at: http://i.imgur.com/GFZ1gSq.jpg My kernel config is attached. The kernel version is 3.15.6-gentoo. When I disassemble at the location of the panic, I get this: (gdb) disas /m file_free_rcu Dump of assembler code for function file_free_rcu: 0xffffffff8111f0e0 <+0>: push %rbx 0xffffffff8111f0e1 <+1>: mov %rdi,%rbx 0xffffffff8111f0e4 <+4>: mov 0xa0(%rdi),%rdi 0xffffffff8111f0eb <+11>: lock decl (%rdi) 0xffffffff8111f0ee <+14>: je 0xffffffff8111f100 <file_free_rcu+32> 0xffffffff8111f0f0 <+16>: mov 0x8d2f69(%rip),%rdi # 0xffffffff819f2060 <filp_cachep> 0xffffffff8111f0f7 <+23>: mov %rbx,%rsi 0xffffffff8111f0fa <+26>: pop %rbx 0xffffffff8111f0fb <+27>: jmpq 0xffffffff81119db0 <kmem_cache_free> 0xffffffff8111f100 <+32>: callq 0xffffffff81061e10 <__put_cred> 0xffffffff8111f105 <+37>: mov %rbx,%rsi 0xffffffff8111f108 <+40>: mov 0x8d2f51(%rip),%rdi # 0xffffffff819f2060 <filp_cachep> 0xffffffff8111f10f <+47>: pop %rbx 0xffffffff8111f110 <+48>: jmpq 0xffffffff81119db0 <kmem_cache_free> End of assembler dump. So the panic is at a "lock decl" instruction. I don't know why, but CONFIG_DEBUG_INFO isn't set, so I can't match them up line for line, but here's the source: static void file_free_rcu(struct rcu_head *head) { struct file *f = container_of(head, struct file, f_u.fu_rcuhead); put_cred(f->f_cred); kmem_cache_free(filp_cachep, f); }
The "lock decl" is in atomic_dec_and_test, which is inside of put_cred.
1) Please post your `emerge --info' output in a comment. 2) Please attach all relevant files /directly/ to this bug report.
================================================================= System uname: Linux-3.16.0-gentoo-x86_64-Intel-R-_Core-TM-_i5-4430_CPU_@_3.00GHz-with-gentoo-2.2 KiB Mem: 8020420 total, 477304 free KiB Swap: 33554428 total, 33554428 free Timestamp of tree: Thu, 14 Aug 2014 07:00:01 +0000 ld GNU ld (Gentoo 2.24 p1.4) 2.24 app-shells/bash: 4.2_p47 dev-lang/python: 2.7.8, 3.3.5-r1, 3.4.1 dev-util/cmake: 2.8.12.2-r1 dev-util/pkgconfig: 0.28-r2 sys-apps/baselayout: 2.2 sys-apps/openrc: 0.12.4 sys-apps/sandbox: 2.6-r1 sys-devel/autoconf: 2.69 sys-devel/automake: 1.11.6, 1.14.1 sys-devel/binutils: 2.24-r3 sys-devel/gcc: 4.8.3 sys-devel/gcc-config: 1.8 sys-devel/libtool: 2.4.2-r1 sys-devel/make: 4.0-r1 sys-kernel/linux-headers: 3.16 (virtual/os-headers) sys-libs/glibc: 2.19-r1 Repositories: gentoo ACCEPT_KEYWORDS="amd64 ~amd64" ACCEPT_LICENSE="*" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-O2 -march=native -ggdb -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /usr/share/gnupg/qualified.txt" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo /etc/texmf/language.dat.d /etc/texmf/language.def.d /etc/texmf/updmap.d /etc/texmf/web2c" CXXFLAGS="-O2 -march=native -ggdb -pipe" DISTDIR="/usr/portage/distfiles" EMERGE_DEFAULT_OPTS="--jobs=4" FCFLAGS="-O2 -pipe" FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync news parallel-fetch preserve-libs protect-owned sandbox sfperms splitdebug strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync" FFLAGS="-O2 -pipe" GENTOO_MIRRORS="rsync://mirror.mcs.anl.gov/gentoo/ rsync://rsync.gtlib.gatech.edu/gentoo rsync://mirrors.rit.edu/gentoo/ http://gentoo.osuosl.org/ http://gentoo.netnitco.net http://mirror.csclub.uwaterloo.ca/gentoo-distfiles/ ftp://mirror.datapipe.net/gentoo ftp://mirror.csclub.uwaterloo.ca/gentoo-distfiles/ http://gentoo.mirrors.easynews.com/linux/gentoo/ ftp://ftp.free.fr/mirrors/ftp.gentoo.org/ ftp://gentoo.imj.fr/pub/gentoo/ ftp://distro.ibiblio.org/pub/linux/distributions/gentoo/" LANG="en_US.UTF-8" LDFLAGS="-Wl,-O1 -Wl,--as-needed" MAKEOPTS="--jobs=2" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_EXTRA_OPTS="-4" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" PORTDIR_OVERLAY="" SYNC="rsync://rsync.gentoo.org/gentoo-portage" USE="X a52 acl ads amd64 avahi avi avx avx256 berkdb bzip2 cairo caps caps-ng cli cpumining cracklib crypt cxx dbus divx dri dv dvd dvdread encode fame fortran gdbm iconv ipv6 jpeg keymap kvm ldap lm_sensors mjpeg mmx modules mp3 mpeg multilib ncurses nls nptl ogg openmp pam parse-clocks pcre png python quicktime readline session sse sse2 sse3 ssl subtitles tcpd unicode upcall vorbis winbind xvid zlib" ABI_X86="64" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="kexi words flow plan sheets stage tables krita karbon braindump author" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf superstar2 timing tsip tripmate tnt ublox ubx" INPUT_DEVICES="evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" LINGUAS="en en_US" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-3 php5-4" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7 python3_3" QEMU_SOFTMMU_TARGETS="i386 x86_64" QEMU_USER_TARGETS="i386 x86_64" RUBY_TARGETS="ruby19 ruby20 ruby21" USERLAND="GNU" VIDEO_CARDS="intel" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" Unset: CPPFLAGS, CTARGET, INSTALL_MASK, LC_ALL, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, USE_PYTHON
Created attachment 382912 [details] Screen photo of panic
Is this still an issue with later kernels?
