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It turns out that the recent changes to alternatives > opened a race window where interrupts are enabled and NOPs are optimized in > place. An interrupt hitting into the modification will observe inconsistent > text and crash and burn. > > A 32bit QEMU crashes w/o these fixes reliably within about 50 boot > attempts. With the fix applied it survived close to 600 attempts by > now. I can confirm that - since I was already set up for it, I let it run overnight for about 1250 attempts. With an average of one in 200 that I was seeing before, I should have had around six fails. Didn't see one. > Thanks to Paul for providing all the information! On behalf of Richard and myself, thanks for the complex fix. Paul. -- > > Thanks, > > tglx > >