Messages in this thread | | | Date | Wed, 8 Jul 2015 11:17:38 -0400 (EDT) | From | Mikulas Patocka <> | Subject | Kernel broken on processors without performance counters |
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Hi
I found out that the patch a66734297f78707ce39d756b656bfae861d53f62 breaks the kernel on processors without performance counters, such as AMD K6-3. Reverting the patch fixes the problem.
The static key rdpmc_always_available somehow gets set (I couldn't really find out what is setting it, the function set_attr_rdpmc is not executed), cr4_set_bits(X86_CR4_PCE) is executed and that results in a crash on boot when attempting to execute init, because the proecssor doesn't support that bit in CR4.
Mikulas
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