From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Fri, 18 Dec 2015 09:34:12 +0000 Subject: [PATCH 2/2] ARM: Make IPI_CPU_BACKTRACE a "non-secure" SGI In-Reply-To: <1450430173-26992-3-git-send-email-marc.zyngier@arm.com> References: <1450430173-26992-1-git-send-email-marc.zyngier@arm.com> <1450430173-26992-3-git-send-email-marc.zyngier@arm.com> Message-ID: <20151218093412.GN8644@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Dec 18, 2015 at 09:16:13AM +0000, Marc Zyngier wrote: > Having IPI_CPU_BACKTRACE as SGI15 may not work if the kernel is > running in non-secure mode and that the secure firmware has > decided to follow ARM's recommendations that SGI8-15 should > be reserved for secure purpose. > > Now that we are "only" using SGI0-6, change IPI_CPU_BACKTRACE > to use SGI7, which makes it more likely to work. We should add a comment to the enum explaining this, so it's obvious for the future - best place is after the IPI_CPU_BACKTRACE entry. Not everyone checks the git logs for these kinds of details. -- RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.