[Bug runtime/14781] New: kmem_cache conflict leads to panic & badness

["fche at redhat dot com" <sourceware-bugzilla at sourceware dot org>]

http://sourceware.org/bugzilla/show_bug.cgi?id=14781

             Bug #: 14781
           Summary: kmem_cache conflict leads to panic & badness
           Product: systemtap
           Version: unspecified
            Status: NEW
          Severity: normal
          Priority: P2
         Component: runtime
        AssignedTo: systemtap@sourceware.org
        ReportedBy: fche@redhat.com
    Classification: Unclassified


While running two copies of the testsuite on a 3.7-rc2 kernel, the following
kernel messages appeared.  There appear to be two separate problems:

[ 3674.684704] stap_96bb7c5e58aa58813663912db0a39d5_31321: systemtap:
2.1/0.155, base: f8108000, memory: 46data/44text/8ctx/2058net/17alloc kb,
probes: 4
[ 3674.687356] kmem_cache_sanity_check (utrace): Cache name already exists.
[ 3674.688384] Pid: 31321, comm: stapio Tainted: GF           
3.7.0-0.rc2.git1.2.fc19.i686.PAE #1
[ 3674.690306] Call Trace:
[ 3674.690933]  [<c055211d>] kmem_cache_create+0x1bd/0x290
[ 3674.691725]  [<f8110796>] utrace_init+0x56/0x200
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.693099]  [<f8111fe5>] _stp_ctl_write_cmd+0xa55/0xf90
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.694493]  [<f8108000>] ? 0xf8107fff
[ 3674.695220]  [<c058ce93>] ? rw_verify_area+0x63/0x110
[ 3674.696002]  [<f8111590>] ? stapiu_process_found+0x3b0/0x3b0
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.697416]  [<c058cfcc>] vfs_write+0x8c/0x160
[ 3674.698193]  [<f8111590>] ? stapiu_process_found+0x3b0/0x3b0
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.699647]  [<c058d2c7>] sys_write+0x47/0x80
[ 3674.700475]  [<c0a2f8e7>] syscall_call+0x7/0xb

wherein the KMEM_CACHE names in runtime/linux/stp_utrace.c are not unique
across the system (but should be), and:

[ 3674.701316] BUG: unable to handle kernel NULL pointer dereference at
00000004
[ 3674.702234] IP: [<c0577363>] kmem_cache_alloc+0x43/0x250
[ 3674.702234] *pdpt = 0000000022e22001 *pde = 0000000000000000 
[ 3674.702234] Oops: 0000 [#1] SMP 
[ 3674.702234] Modules linked in: stap_96bb7c5e58aa58813663912db0a39d5_31321(F)
stap_ee78b61c762c8440fdc83c112ac2caa_28780(F) nfsv4(F) auth_rpcgss(F) nfs(F)
dns_resolver(F) fscache(F) xt_nat(F) iptable_nat(F) nf_conntrack_ipv4(F)
nf_defrag_ipv4(F) nf_nat_ipv4(F) nf_nat(F) nf_conntrack(F) lockd(F) sunrpc(F)
bnep(F) bluetooth(F) rfkill(F) ppdev(F) 8139too(F) microcode(F) 8139cp(F)
i2c_piix4(F) i2c_core(F) mii(F) parport_pc(F) parport(F) uinput(F) [last
unloaded: stap_1ad36db660f97e42f17adf8e9f09ce2_27751]
[ 3674.702234] Pid: 31321, comm: stapio Tainted: GF           
3.7.0-0.rc2.git1.2.fc19.i686.PAE #1 Bochs Bochs
[ 3674.702234] EIP: 0060:[<c0577363>] EFLAGS: 00010246 CPU: 1
[ 3674.702234] EIP is at kmem_cache_alloc+0x43/0x250
[ 3674.702234] EAX: 00000286 EBX: 000080c0 ECX: e23c5640 EDX: 00000000
[ 3674.702234] ESI: 00000000 EDI: 00000000 EBP: e22bdec0 ESP: e22bde94
[ 3674.702234]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[ 3674.702234] CR0: 8005003b CR2: 00000004 CR3: 23c2a000 CR4: 000006f0
[ 3674.702234] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[ 3674.702234] DR6: ffff0ff0 DR7: 00000400
[ 3674.702234] Process stapio (pid: 31321, ti=e22bc000 task=e23c5640
task.ti=e22bc000)
[ 3674.702234] Stack:
[ 3674.702234]  00000246 f8109f98 f8116100 e23c0000 f810bea7 000080c0 c0a2f4c2
00000000
[ 3674.702234]  00000001 00000000 f8116560 e22bdee0 f810bea7 e22bdf00 e23c0000
00000010
[ 3674.702234]  00000001 e23c0000 f602aa40 e22bdf00 f81101a6 00000000 00000000
c0cab60c
[ 3674.702234] Call Trace:
[ 3674.702234]  [<f8109f98>] ? task_utrace_struct+0x28/0x30
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<f810bea7>] ? utrace_attach_task+0x167/0x260
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<c0a2f4c2>] ? _raw_spin_unlock+0x22/0x30
[ 3674.702234]  [<f810bea7>] utrace_attach_task+0x167/0x260
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<f81101a6>] __stp_utrace_attach+0x56/0x1c0
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<f8112158>] _stp_ctl_write_cmd+0xbc8/0xf90
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<f8112037>] ? _stp_ctl_write_cmd+0xaa7/0xf90
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<f8111590>] ? stapiu_process_found+0x3b0/0x3b0
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<c058cfcc>] vfs_write+0x8c/0x160
[ 3674.702234]  [<f8111590>] ? stapiu_process_found+0x3b0/0x3b0
[stap_96bb7c5e58aa58813663912db0a39d5_31321]
[ 3674.702234]  [<c058d2c7>] sys_write+0x47/0x80
[ 3674.702234]  [<c0a2f8e7>] syscall_call+0x7/0xb
[ 3674.702234] Code: d3 89 c7 89 d8 89 55 e8 89 4d e4 e8 48 7b f4 ff f6 c3 10
74 16 31 c9 ba a0 03 00 00 b8 c5 8b bc c0 e8 42 44 f1 ff e8 9d 67 4b 00 <8b> 4f
04 89 da 8b 47 10 e8 30 2b 00 00 84 c0 0f 85 40 01 00 00
[ 3674.702234] EIP: [<c0577363>] kmem_cache_alloc+0x43/0x250 SS:ESP
0068:e22bde94
[ 3674.702234] CR2: 0000000000000004
[ 3674.758288] ---[ end trace 87295d07a258be60 ]---

wherein a subsequent allocation attempt goes south, way south, way way WAY
south, where even penguins don't dare to tread.

-- 
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.