From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Fri, 6 Oct 2017 14:13:44 +0100 Subject: undefined instruction d5380001 (arm64 mrs emulation) In-Reply-To: References: <20171002112433.GM3611@e103592.cambridge.arm.com> <59D24906.4060104@arm.com> <20171002155638.GA18543@e107814-lin.cambridge.arm.com> <20171005161645.7sqjkd25pwdng5dz@armageddon.cambridge.arm.com> Message-ID: <20171006131343.rs7ig4owz4anw3cl@armageddon.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Oct 06, 2017 at 02:05:09PM +0200, Matthias Brugger wrote: > On 10/05/2017 06:16 PM, Catalin Marinas wrote: > > On Thu, Oct 05, 2017 at 04:54:09PM +0200, Matthias Brugger wrote: > > > We also hit this bug in openSUSE Tumbleweed: > > > https://bugzilla.suse.com/show_bug.cgi?id=1061188 > > > > As Mark replied, we are still debating why this happens and whether the > > above fix is sufficient. As we were digging further, we realised there > > is no clear init level after which user space can be invoked, which > > means Suzuki's patch may not always be sufficient. > > > > I proposed something as a way of spotting this issue early [1] but I > > need to post it on the linux-arch to get some consensus. > > > > Can you post the full kernel log somewhere? I'm trying to figure out > > what trigged the modprobe during the kernel boot. > > > > You can find the kernel log here: > https://bugzilla.suse.com/attachment.cgi?id=743311 Thanks, it seems that ipv6 module loading triggered this. Talking to Suzuki, we came to the conclusion that such thing cannot happen before rootfs_initcall, so his original core_initcall change should suffice. I'll push a patch out, hopefully for -rc4 and cc stable. -- Catalin