From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Sun, 2 Nov 2014 22:14:01 +0000 Subject: Crash on ARM: 8148/1 flush TLS and thumbee register In-Reply-To: <3b91528704d24eb119ec6d80ad6ba07f@agner.ch> References: <5425DA4D.4040301@mentor.com> <3b91528704d24eb119ec6d80ad6ba07f@agner.ch> Message-ID: <20141102221401.GA4042@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sun, Nov 02, 2014 at 11:03:14PM +0100, Stefan Agner wrote: > Hi all, > > While working on Vybrid (vf610) Cortex-M4 support I also hit this crash > observed by Joachim: > > ... > Freeing unused kernel memory: 16K (8800a000 - 8800e000) > > Unhandled exception: IPSR = 00000005 LR = fffffff1 > CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216 > task: 8b838000 ti: 8b82a000 task.ti: 8b82a000 > PC is at flush_thread+0x32/0x40 > LR is at flush_thread+0x21/0x40 > pc : [<8f00157a>] lr : [<8f001569>] psr: 4100000b > sp : 8b82be20 ip : 00000000 fp : 8b83c000 > r10: 00000001 r9 : 88018c84 r8 : 8bb85000 > r7 : 8b838000 r6 : 00000000 r5 : 8bb77400 r4 : 8b82a000 > r3 : ffff0ff0 r2 : 8b82a000 r1 : 00000000 r0 : 88020354 > xPSR: 4100000b > CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc1-00041-ga30465a #216 > [<8f002bc1>] (unwind_backtrace) from [<8f002033>] (show_stack+0xb/0xc) > [<8f002033>] (show_stack) from [<8f00265b>] (__invalid_entry+0x4b/0x4c) > > Can reproduce it on 3.18-rc1, as well as 3.17. Hmm, I think KUSER_HELPERS needs to depend on MMU. Nathan? -- FTTC broadband for 0.8mile line: currently at 9.5Mbps down 400kbps up according to speedtest.net.