lkml.org 
[lkml]   [2005]   [Apr]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: 2.6.12-rc2-mm3
    Borislav Petkov <petkov@uni-muenster.de> wrote:
    >
    > On Monday 11 April 2005 11:43, Andrew Morton wrote:
    > > (Please do reply-to-all)
    > >
    > > "J.A. Magallon" <jamagallon@able.es> wrote:
    > > > On 04.11, Andrew Morton wrote:
    > > > > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.12-r
    > > > >c2/2.6.12-rc2-mm3/
    > > >
    > > > Is this not needed anymore ?
    > > >
    > > > --- 25/arch/i386/kernel/entry.S~nmi_stack_correct-fix 2005-04-05
    > > > 00:02:48.000000000 -0700 +++ 25-akpm/arch/i386/kernel/entry.S 2005-04-05
    > > > 00:02:48.000000000 -0700
    > >
    > > Hopefully not. fix-crash-in-entrys-restore_all.patch works around the
    > > problem. -
    >
    > Hello Andrew,
    > I don't know whether you remember the mysterious crashes I was telling you
    > about last week and me rookiesh-ly trying to debug them with kgdb over the
    > serial console. Well, today I tried for the n-th time again and after rc2-mm3
    > blocked again while loading, here's what I did:
    >
    > <snip>
    > [ 12.335438] NET: Registered protocol family 17
    > [ 12.362483] Testing NMI watchdog ... OK.
    > [ 12.416195] Starting balanced_irq
    > [ 12.443099] VFS: Mounted root (ext2 filesystem) readonly.
    > [ 12.472490] Freeing unused kernel memory: 196k freed
    > [ 12.521004] logips2pp: Detected unknown logitech mouse model 1
    > [ 12.572581] Warning: unable to open an initial console.
    > [ 12.972518] input: PS/2 Logitech Mouse on isa0060/serio1
    >
    > Program received signal SIGTRAP, Trace/breakpoint trap.
    > 0xc0102ee7 in resume_kernelX () at atomic.h:175 <--- this one is wrong for a
    > mysterious reason
    > 175 {
    > (gdb) p $eip
    > $1 = (void *) 0xc0102ee7
    >
    > (gdb) disas 0xc0102ee7
    > Dump of assembler code for function resume_kernelX:
    > 0xc0102ee7 <resume_kernelX+0>: mov 0x30(%esp),%eax
    > 0xc0102eeb <resume_kernelX+4>: mov 0x38(%esp),%ah
    > 0xc0102eef <resume_kernelX+8>: mov 0x2c(%esp),%al
    > 0xc0102ef3 <resume_kernelX+12>: and $0x20403,%eax
    > 0xc0102ef8 <resume_kernelX+17>: cmp $0x403,%eax
    > 0xc0102efd <resume_kernelX+22>: je 0xc0102f0c <ldt_ss>
    > End of assembler dump.
    > (gdb)
    >
    > And as we see, we're at the "mov 0x30(%esp),%eax" which accesses above the
    > bottom of the stack. After applying nmi_stack_correct-fix.patch, rc2-mm3
    > booted just fine, so I IMHO think that we might still be needing this, after
    > all.

    Interesting. It could be an interaction between the kgdb patch and the new
    vm86 checking code. (looks. I don't think that's the case).

    Stas, could you please take a look at 2.6.12-rc2-mm3's entry.S sometime,
    see if you think my theory is correct?

    It seems that you have CONFIG_TRAP_BAD_SYSCALL_EXITS enabled - I can't say
    that I've ever used that, and I really should remove it. But I doubt if
    that is the cause of this bug.


    The above code is accessing esp+56, but Stas's patch only offsets the stack
    pointer by 32 bytes, so I assume this, in copy_thread():

    - p->thread.esp0 = (unsigned long) (childregs+1) - 8;
    + p->thread.esp0 = (unsigned long) (childregs+1) - 15;

    fixes it?
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-04-12 00:32    [W:0.027 / U:1.320 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site