[Bug tapsets/19057] New: _is_reset() can crash the rhel6 / s390 kernel

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

https://sourceware.org/bugzilla/show_bug.cgi?id=19057

            Bug ID: 19057
           Summary: _is_reset() can crash the rhel6 / s390 kernel
           Product: systemtap
           Version: unspecified
            Status: NEW
          Severity: normal
          Priority: P2
         Component: tapsets
          Assignee: systemtap at sourceware dot org
          Reporter: mcermak at redhat dot com
  Target Milestone: ---

With stap release-2.9-4-g4dc97b40ad9e, `stap -ge 'probe oneshot
{println(_is_reset(0))}'` kills the rhel6/s390 kernel (2.6.32-573.el6). Not
always, but two or three attempts are usually enough:

=======
Unable to handle kernel pointer dereference at virtual kernel address
0000000098
000000
Oops: 003b [#1] SMP
Modules linked in: stap_52c42bc8bfec93176c3b72de4b42cbe6__2581(U) ipv6 qeth_l2
v
mur qeth qdio lcs ctcm fsm ccwgroup ext4 jbd2 mbcache dasd_fba_mod
dasd_eckd_mod
 dasd_mod dm_mirror dm_region_hash dm_log dm_mod [last unloaded:
stap_52c42bc8bf
ec93176c3b72de4b42cbe6__2574]
CPU: 0 Not tainted 2.6.32-573.el6.s390x #1
Process stapio (pid: 2581, task: 0000000001ae7370, ksp: 000000007c28ba20)
Krnl PSW : 0704000180000000 000003e000af7440 (probe_2781+0x220/0x544
[stap_52c42
bc8bfec93176c3b72de4b42cbe6__2581])
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:0 PM:0 EA:3
Krnl GPRS: 0000000000000010 000000007b9b41c7 0000000000000000 0000000000000000
           0000000000000001 3510000000000000 0000000098000000 0000000000000001
           0000000000000001 00000000000000d0 000003e000d11470 000000007c28bd90
           000003e000af5000 000003e000afea78 000003e000af771e 000000007c28bcd8
Krnl Code: 000003e000af7434: eb77b000002f       lctlg   ,7,A7,0(%r11)
           000003e000af743a: 1222               ltr     %r2,%r2
           000003e000af743c: a7740148           brc     7,3e000af76cc
          >000003e000af7440: 5816300c           l       %r1,12(%r6,%r3)
           000003e000af7444: 88100012           srl     %r1,18
           000003e000af7448: e310d0000080       ng      %r1,0(%r13)
           000003e000af744e: e310a0080024       stg     %r1,8(%r10)
           000003e000af7454: a7f40057           brc     15,3e000af7502
Call Trace:
([<000003e000af73e8>] probe_2781+0x1c8/0x544
[stap_52c42bc8bfec93176c3b72de4b42c
be6__2581])
 [<000003e000afb156>] enter_be_probe+0x1b2/0x2e4
[stap_52c42bc8bfec93176c3b72de4
b42cbe6__2581]
 [<000003e000afc6ca>] _stp_ctl_write_cmd+0x942/0xa44
[stap_52c42bc8bfec93176c3b7
2de4b42cbe6__2581]
 [<000000000025ddc4>] vfs_write+0xa0/0x1a0
 [<000000000025dfc2>] SyS_write+0x5a/0xc4
 [<0000000000119ba4>] sysc_tracego+0xe/0x14
 [<000003fffd7074ac>] 0x3fffd7074ac
Last Breaking-Event-Address:
 [<000003e000af7730>] probe_2781+0x510/0x544
[stap_52c42bc8bfec93176c3b72de4b42c
be6__2581]

Kernel panic - not syncing: Fatal exception: panic_on_oops
CPU: 0 Tainted: G      D    -- ------------    2.6.32-573.el6.s390x #1
Process stapio (pid: 2581, task: 0000000001ae7370, ksp: 000000007c28ba20)
000000007c28b970 000000007c28b8f0 0000000000000002 0000000000000000
       000000007c28b990 000000007c28b908 000000007c28b908 00000000004f67a8
       000000007fe4458e 0000000000000000 000000000004003b 00000000000001d8
       000000000000000d 000000000000000c 000000007c28b960 0000000000000000
       0000000000000000 000000000010582c 000000007c28b8f0 000000007c28b930
Call Trace:
([<000000000010572c>] show_trace+0xe8/0x138)
 [<00000000004f65e2>] panic+0xde/0x250
 [<0000000000105d84>] die+0x174/0x180
 [<000000000010132e>] do_no_context+0xae/0xec
 [<00000000004fb4aa>] do_dat_exception+0x212/0x310
 [<0000000000119d54>] pgm_exit+0x0/0x4
 [<000003e000af7440>] probe_2781+0x220/0x544
[stap_52c42bc8bfec93176c3b72de4b42c
be6__2581]
([<000003e000af73e8>] probe_2781+0x1c8/0x544
[stap_52c42bc8bfec93176c3b72de4b42c
be6__2581])01: HCPGSP2629I The virtual machine is placed in CP mode due to a
SIG
P stop from
 CPU 01.

 [<000003e000afb156>] enter_be_probe+0x1b2/0x2e4
[stap_52c42bc8bfec93176c3b72de4
b42cbe6__2581]
 [<000003e000afc6ca>] _stp_ctl_write_cmd+0x942/0xa44
[stap_52c42bc8bfec93176c3b7
2de4b42cbe6__2581]
 [<000000000025ddc4>] vfs_write+0xa0/0x1a0
 [<000000000025dfc2>] SyS_write+0x5a/0xc4
 [<0000000000119ba4>] sysc_tracego+0xe/0x14
 [<000003fffd7074ac>] 0x3fffd7074ac
00: HCPGIR450W CP entered; disabled wait PSW 00020001 80000000 00000000
001156BA
=======

-- 
You are receiving this mail because:
You are the assignee for the bug.