> On Mar 6, 2020, at 7:03 PM, Anshuman Khandual <Anshuman.Khandual@xxxxxxx> wrote: > > Hmm, set_pte_at() function is not preferred here for these tests. The idea > is to avoid or atleast minimize TLB/cache flushes triggered from these sort > of 'static' tests. set_pte_at() is platform provided and could/might trigger > these flushes or some other platform specific synchronization stuff. Just Why is that important for this debugging option? > wondering is there specific reason with respect to the soft lock up problem > making it necessary to use set_pte_at() rather than a simple WRITE_ONCE() ? Looks at the s390 version of set_pte_at(), it has this comment, vmaddr); /* * Certain architectures need to do special things when PTEs * within a page table are directly modified. Thus, the following * hook is made available. */ I can only guess that powerpc could be the same here.
