Messages in this thread | | | Subject | Re: BUG: unable to handle kernel paging request at ffffc7ff81000398 (sys_kexec_load) | From | Sasha Levin <> | Date | Sat, 28 Jan 2012 10:11:30 -0500 |
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On Sat, 2012-01-21 at 20:49 -0800, Eric W. Biederman wrote: > Interesting. > > The fact that this happens in native_set_pte would suggest that we are > trying to write to a page table that does not exist. So this might > be a layer below kexec_load that has the problem. > > Do you have the kernel you were testing? A disassembly of the > native_set_pte, machine_kexec_prepare and sys_kexec_load > would be interesting, for attempting to trace this back to what went > wrong.
I did some work into investigating it today, looks like it's simple to trigger it using the following code:
#include <fcntl.h> int main(void) { char dummy[4096] = {0}; syscall(246, 0xffffffff81008000, 1, dummy, 2); return 0; }
I'll continue trying to figure out whats wrong, but hopefully this lead will help in reproducing it easily.
--
Sasha.
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