On Tue, 15 Nov 2016 07:35:54 -0800 Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > Hi Martin, > > my s390 qemu boot test crashes in -next as follows. > > Kernel stack overflow. > CPU: 0 PID: 923 Comm: modprobe Not tainted 4.9.0-rc5-next-20161115 #1 > Hardware name: QEMU QEMU QEMU (KVM) > task: 000000001d805100 task.stack: 000000001d898000 > Krnl PSW : 0404e00180000000 0000000000ac2b42 (pgm_check_handler+0xd6/0x1b4) > R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 > Krnl GPRS: 0000000000000020 0000000000000000 0000000000000004 0000000000000000 > 0000000000400034 0000000000000000 000000007ff3b350 0000000000000001 > 0404e00180000000 0000000000ac2b42 0000000000ac2ad0 000000007ff38178 > 000000001d805100 0000000000ac335e 0000000000000200 000000007ff380d8 > Krnl Code: 0000000000ac2b34: a7840005 brc 8,ac2b3e > 0000000000ac2b38: d2ffe0e8d000 mvc 232(256,%r14),0(%r13) > #0000000000ac2b3e: 41b0f0a0 la %r11,160(%r15) > >0000000000ac2b42: eb07b0180024 stmg %r0,%r7,24(%r11) > 0000000000ac2b48: d23fb0580200 mvc 88(64,%r11),512 > 0000000000ac2b4e: eb89b0080024 stmg %r8,%r9,8(%r11) > 0000000000ac2b54: d203b0a0008c mvc 160(4,%r11),140 > 0000000000ac2b5a: d207b0a800a8 mvc 168(8,%r11),168 > Call Trace: > no locks held by modprobe/923. > Last Breaking-Event-Address: > [<0000000000000000>] (null) > Kernel panic - not syncing: Corrupt kernel stack, can't continue. > > Bisect points to commit 1914608db9 ("s390: move sys_call_table and last_break > from thread_info to thread_struct"). Reverting that patch fixes the problem. > > Configuration is s390:defconfig with CONFIG_MARCH_Z900=y. > > Bisect log is attached. > A complete log is at: > http://kerneltests.org/builders/qemu-s390-next/builds/252/steps/qemubuildcommand/logs/stdio Thanks for the report. Builds for Z900 and Z990 are borked. This hunk @@ -287,7 +292,13 @@ ENTRY(system_call) mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC stg %r14,__PT_FLAGS(%r11) .Lsysc_do_svc: - lg %r10,__TI_sysc_table(%r12) # address of system call table + # load address of system call table +#ifdef CONFIG_HAVE_MARCH_Z990_FEATURES + lg %r10,__TASK_thread+__THREAD_sysc_table(%r12) +#else + lghi %r10,__TASK_thread + lg %r10,__THREAD_sysc_table(%r10,%r12) +#endif llgh %r8,__PT_INT_CODE+2(%r11) slag %r8,%r8,2 # shift and test for svc 0 jnz .Lsysc_nr_ok makes ill use of %r10 in the #else part. Should be fixed now and tomorrows -next tree will have the fix. Thanks again. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html