Vivek Goyal napisał(a): > On Thu, Mar 22, 2007 at 02:27:25PM +0100, Michal Piotrowski wrote: >> Michal Piotrowski napisał(a): >>> On 22/03/07, Ingo Molnar <[EMAIL PROTECTED]> wrote: >>>> * Michal Piotrowski <[EMAIL PROTECTED]> wrote: >>>> >>>>> Hi Ingo, >>>>> 2.6.21-rc4-rt0 >>>>> BUG: at kernel/fork.c:1033 copy_process() >>>> thanks Michal - this is a real bug that affects upstream too. Find the >>>> fix below - i've test-booted it and it fixes the warning. >>> Problem is fixed, thanks. >> BTW. It seems that nobody uses -rt as a crash dump kernel ;) >> >> BUG: unable to handle kernel paging request at virtual address f7ebf8c4 >> printing eip: >> c1610192 >> *pde = 00000000 >> stopped custom tracer. >> Oops: 0000 [#1] >> PREEMPT >> Modules linked in: >> CPU: 0 >> EIP: 0060:[<c1610192>] Not tainted VLI >> EFLAGS: 00010206 (2.6.21-rc4-rt0-kdump #3) >> EIP is at copy_oldmem_page+0x4a/0xd0 >> eax: 000008c4 ebx: f7ebf000 ecx: 00000100 edx: 00000246 >> esi: f7ebf8c4 edi: c4c520fc ebp: c4d54e30 esp: c4d54e18 >> ds: 007b es: 007b fs: 00d8 gs: 0000 ss: 0068 preempt:00000001 >> Process swapper (pid: 1, ti=c4d54000 task=c4d52c20 task.ti=c4d54000) >> Stack: c17ab7e0 c183f982 c1969658 00000400 00000400 00037ebf c4d54e5c >> c16af187 >> 00037ebf c4c520fc 00000400 000008c4 00000000 00000000 c4c696e0 >> 00000400 >> c4c520fc c4d54f94 c19a9cfd c4c520fc 00000400 c4d54f78 00000000 >> c1840996 >> Call Trace: >> [<c16af187>] read_from_oldmem+0x73/0x98 >> [<c19a9cfd>] vmcore_init+0x26c/0xab7 >> [<c199979b>] init+0xaa/0x287 >> [<c16044eb>] kernel_thread_helper+0x7/0x10 >> ======================= >> >> l *copy_oldmem_page+0x4a/0xd0 >> 0xc1610148 is in copy_oldmem_page (arch/i386/kernel/crash_dump.c:35). >> 30 * copying the data to a pre-allocated kernel page and then copying >> to user >> 31 * space in non-atomic context. >> 32 */ >> 33 ssize_t copy_oldmem_page(unsigned long pfn, char *buf, >> 34 size_t csize, unsigned long offset, >> int userbuf) >> 35 { >> 36 void *vaddr; >> 37 >> 38 if (!csize) >> 39 return 0; >> > > Can you please paste the disassembly of copy_oldmem_page() on your system. > Not sure from where this faulting address 0xf7ebf8c4 is coming. We are still > in vmcore_init(), so we should be copying the data to kernel buffers only. > This looks like a valid kernel address. > > Can you also put some printk() here to find out from where 0xf7ebf8c4 has > come? It does not look like a fixed kernel virutual address returned by > kmap_atomic_pfn(). Then is it passed by kernel as a parameter to > copy_oldmem_page()?
I added printk(KERN_WARNING "copy_oldmem_page() pfn=%lu , buf=%s , nr_bytes=%d , offset=%lu , userbuf=%d\n", pfn, buf, nr_bytes, offset, userbuf); before tmp = copy_oldmem_page(pfn, buf, nr_bytes, offset, userbuf); result is here http://www.stardust.webpages.pl/files/tbf/bitis-gabonica/2.6.21-rc4-rt0/kdump-console2.log 'buf' might be broken. > > Thanks > Vivek > Regards, Michal -- Michal K. K. Piotrowski LTG - Linux Testers Group (PL) (http://www.stardust.webpages.pl/ltg/) LTG - Linux Testers Group (EN) (http://www.stardust.webpages.pl/linux_testers_group_en/) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/