On 7/10/19 11:57 AM, Christophe Leroy wrote: > > > Le 10/07/2019 à 06:54, Ravi Bangoria a écrit : >> On Powerpc64, watchpoint match range is double-word granular. On >> a watchpoint hit, DAR is set to the first byte of overlap between >> actual access and watched range. And thus it's quite possible that >> DAR does not point inside user specified range. Ex, say user creates >> a watchpoint with address range 0x1004 to 0x1007. So hw would be >> configured to watch from 0x1000 to 0x1007. If there is a 4 byte >> access from 0x1002 to 0x1005, DAR will point to 0x1002 and thus >> interrupt handler considers it as extraneous, but it's actually not, >> because part of the access belongs to what user has asked. So, let >> kernel pass it on to user and let user decide what to do with it >> instead of silently ignoring it. The drawback is, it can generate >> false positive events. > > Why adding some #ifdefs based on CONFIG_8xx ?
I don't know how 8xx behaves so I'm keeping the current behavior(ignore extraneous exception) for 8xx. > > I see your commit log mentions 'Powerpc64'. What about BOOK3S/32 ? Hmm, I should not have mention 64 there. Yes, the change should cover both Books3S/64 and Book3S/32.