[patch 0/2] x86/alternatives: Prevent crash in NOP optimizer

[Thomas Gleixner]

The following series addresses the regression report from Paul on behalf of
the yocto project. 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.

Thanks to Paul for providing all the information!

Thanks,

	tglx