Messages in this thread | | | Date | Sun, 11 May 2008 12:44:30 -0700 | From | Arjan van de Ven <> | Subject | Re: Error in save_stack_trace() on x86_64? |
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Vegard Nossum wrote: > Hi, > > I am having a problem with v2.6.26-rc1 on x86_64. It seems that > save_stack_trace() is not able to follow page fault boundaries, since > all my saved traces look like this: > > RIP: 0010:[<ffffffff8039b004>] [<ffffffff8039b004>] add_uevent_var+0xb4/0x160 > ... > [<ffffffff80221f97>] kmemcheck_read+0x127/0x1e0 > [<ffffffff80222269>] kmemcheck_access+0x179/0x1d0 > [<ffffffff8022231f>] kmemcheck_fault+0x5f/0x80 > [<ffffffff8061cd1e>] do_page_fault+0x4de/0x8d0 > [<ffffffff8061a7d9>] error_exit+0x0/0x51 > [<ffffffffffffffff>] 0xffffffffffffffff > > I have this in my .config: > > CONFIG_STACKTRACE_SUPPORT=y > CONFIG_STACKTRACE=y > ... > CONFIG_FRAME_POINTER=y > ... > CONFIG_DEBUG_INFO=y > > > On 32-bit, I am able to see the calls leading up to the page fault as > well. Did I miss something here?
can you give an example?
if a pagefault happens in userspace this trace looks correct.
if it happens in kernel space... I wonder if the separate exception stack thing is hurting us with the stacks not being properly connected... (but oopses and the like seem to come out just fine so I kinda doubt you're hitting that)
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