Hi, On Tue, Mar 1, 2011 at 12:35 AM, Robert ÅwiÄcki <robert@xxxxxxxxxxx> wrote: >> But rather than exporting the notion of restart_addr from memory.c, or >> converting to restart_pgoff throughout, simply reset vm_truncate_count >> to 0 to force a rescan if mremap move races with preempted truncation. >> >> We have no confirmation that this fixes Robert's BUG, >> but it is a fix that's worth making anyway. > > Hi, I don't have currently access to my rs232/console testing machine > (lame excuse but it helps a lot;), cause I'm working currently OOtO, > so I'll try to test it asap - which is probably Mar 15th or so. So, I compiled 2.6.38 and started fuzzing it. I'm bumping into other problems, and never seen anything about mremap in 2.6.38 (yet), as it had been happening in 2.6.37-rc2. The output goes to http://alt.swiecki.net/linux_kernel/ - I'm still trying. > Btw, the fuzzer is here: http://code.google.com/p/iknowthis/ > > I think i was trying it with this revision: > http://code.google.com/p/iknowthis/source/detail?r=11 (i386 mode, > newest 'iknowthis' supports x86-64 natively), so feel free to try it. > > It used to crash the machine (it's BUG_ON but the system became > unusable) in matter of hours. Btw, when I was testing it for the last > time it Ooopsed much more frequently in proc_readdir (I sent report in > one of earliet e-mails). > >> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> >> --- >> >> Âmm/mremap.c |  Â4 +--- >> Â1 file changed, 1 insertion(+), 3 deletions(-) >> >> --- 2.6.38-rc6/mm/mremap.c   Â2011-01-18 22:04:56.000000000 -0800 >> +++ linux/mm/mremap.c  2011-02-23 15:29:52.000000000 -0800 >> @@ -94,9 +94,7 @@ static void move_ptes(struct vm_area_str >>         */ >>        Âmapping = vma->vm_file->f_mapping; >>        Âspin_lock(&mapping->i_mmap_lock); >> -        if (new_vma->vm_truncate_count && >> -          new_vma->vm_truncate_count != vma->vm_truncate_count) >> -            new_vma->vm_truncate_count = 0; >> +        new_vma->vm_truncate_count = 0; >>    Â} >> >>    Â/* >> > > > > -- > Robert ÅwiÄcki > -- Robert ÅwiÄcki -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href