From mboxrd@z Thu Jan 1 00:00:00 1970 From: lauraa@codeaurora.org (Laura Abbott) Date: Tue, 25 Nov 2014 10:54:14 -0800 Subject: [PATCHv6 6/8] arm64: use fixmap for text patching when text is RO In-Reply-To: <20141125170445.GB21525@leverpostej> References: <1416606645-25633-1-git-send-email-lauraa@codeaurora.org> <1416606645-25633-7-git-send-email-lauraa@codeaurora.org> <20141125170445.GB21525@leverpostej> Message-ID: <5474D056.2050101@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 11/25/2014 9:04 AM, Mark Rutland wrote: > Hi Laura, > > It looks like "early" means before we've set up the strict page > permissions, though as far as I can tell the fixmap will already be > available before we do any patching. Could we not always use the fixmap > for patching? Then we only need the patch_{map,unmap} additions, and not > the changes to distinguish the early cases. > > From testing on Juno with defconfig, all of the early patches were > avoidable NOP -> NOP changes as part of static key initialisation, which > I think we can skip similarly to x86 (I'll send a patch shortly). All other > patches were not early and went via the fixmap. > > Even with the avoidable NOP -> NOP patching I did not see a noticeable > boot time difference from forcing the use of the fixmap. > I was basing it off of the arm version which needed the early option. If arm64 doesn't need it I'll drop it. > Thanks, > Mark. > Thanks, Laura -- Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project