Balbir Singh <bsinghar...@gmail.com> writes: >>> Changelog: >>> Don't add PAGE_OFFSET blindly, check if REGION_ID is 0 >>> >>> I ran into this issue while debugging an early boot problem. >>> The system hit a BUG_ON() but report bug failed to print the >>> line number and file name. The reason being that the system >>> was running in real mode and report_bug() searches for >>> addresses in the PAGE_OFFSET+ region >>> >>> Suggested-by: Paul Mackerras <pau...@samba.org> >>> Signed-off-by: Balbir Singh <bsinghar...@gmail.com> > > <snip> > >> Can we add some comments around this. When i looked at this first, i was >> wondering how nip can be in user region. But then realized that what we >> are checking here is kernel address used in real mode. The use of >> REGION_ID eventhough simpler is confusing. Hence adding the comment with >> details Paul mentioned in email will help. >> >> > I've tried and covered it in the changelog, I thought a code comment > would make sense for the very non obvious cases and not repeat what > the code does as comment >
The use of REGION_ID indicate that you are checking for region. Hence the suggestion. Looking at this again, I suggest we should add a new macro or will have to open code it. Because in the radix series we make REGION_ID a hash config thing and this is generic stuff. -aneesh _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev