Hi Hisashi, On Fri, Jun 17, 2016 at 10:05 AM, 神田 尚 <[email protected]> wrote: > From: "Hisashi Kanda" <hikanda at zlab dot co dot jp>
Could you please put your real email address here? > I found a logical bug in SPARC code. > So, I send this patch. Please check it. Leave this part out, we only need the explanation of the potential bug, if you're not sure, put any notes like this below the "---". > This bug may occur in the following. > > user_rtt_fill_64bit <= If mna trap occurred, call do_mna > +-> do_mna <= Mistake storing registers for fault code and > address > +-> winfix_mna > +-> user_rtt_fill_fixup <= Put fault address into > thread_info->flag's TI_FAULT_CODE > +-> do_sparc64_fault() <= If fault address has FAULT_CODE_ITLB > and FAULT_CODE_DTLB bits, call BUG() > +-> BUG() > > If mna trap occured in user_rtt_fill_64bit, then do_mna is called. > So, fault address is loaded into %g4, and fault code is loaded into %g5 in > do_mna. > But, %g4 is stored into thread_info->flag's TI_FAULT_CODE, and > %g5 is stored into thread_info->flag's TI_FAULT_ADDR in user_rtt_fill_fixup. > This is a mistake. If fault address has FAULT_CODE_ITLB and > FAULT_CODE_DTLB bits, BUG() may occur in do_sparc64_fault(). > > The patch for this bug is the following. > Kernel version is Linux 4.7-rc3. You should put the kernel version this applies to below the "---". > Signed-off-by: Hisashi Kanda <[email protected]> > > --- i.e. here. Thanks, -- Julian Calaby Email: [email protected] Profile: http://www.google.com/profiles/julian.calaby/
