Messages in this thread | | | Date | Tue, 19 Mar 2013 14:02:34 +0100 | Subject | Re: [PATCH] perf,x86: fix uninitialized pt_regs in intel_pmu_drain_bts_buffer() | From | Stephane Eranian <> |
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On Tue, Mar 19, 2013 at 1:58 PM, Peter Zijlstra <peterz@infradead.org> wrote: > On Tue, 2013-03-19 at 13:50 +0100, Stephane Eranian wrote: >> > Should we not replace: >> > >> > regs.ip = 0; >> > >> > with that memset? It avoids the memset work in a few cases and >> removes >> > the then superfluous clearing of the IP field. >> > >> We could drop it because it's covered by the memset(). > > Yeah, but also place the memset a little lower than you did, avoids the > stack writes when not needed. > Ok, I get it now. Yes, we can move it after the test and drop reg.val = 0.
>> The issue here was that you eventually end up in code_segment_base() >> which >> looks at other uninitialized fields in pt_regs and may cause breakage. > > Right, your changelog said so ;-) >
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