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Message-ID: <53CE4A41.4020605@zytor.com> Date: Tue, 22 Jul 2014 04:25:53 -0700 From: "H. Peter Anvin" <hpa@...or.com> To: Klemen Jan Enova <klemen.jan.enova@...il.com>, linux-kernel@...r.kernel.org CC: mingo@...hat.com, x86@...nel.org Subject: Re: [PATCH] arch: x86: boot: bioscall.S: simplify self-modification of the INT instruction On 07/22/2014 04:01 AM, Klemen Jan Enova wrote: > At the start of the intcall function, the %al register is compared to > 0x3f. If it does not equal 0x3f it is equated to it. Instruction flow > continues in both cases from the label 1. The comparison is therefore > unneeded. > > Testing data is appended. > > Signed-off-and-tested-by: Klemen Jan Enova <klemen.jan.enova@...il.com> NAK. This is a performance optimization - the SMC takes a substantial penalty so the write is avoided if necessary. Also, 3f is a label, not 0x3f. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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