lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 15 Sep 2015 12:30:03 +0100 From: Russell King - ARM Linux <linux@....linux.org.uk> To: Daniel Thompson <daniel.thompson@...aro.org> Cc: linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org, patches@...aro.org, linaro-kernel@...ts.linaro.org, Thomas Gleixner <tglx@...utronix.de>, Hillf Danton <hillf.zj@...baba-inc.com> Subject: Re: [PATCH v2] arm: Fix backtrace generation when IPI is masked On Tue, Sep 15, 2015 at 12:05:12PM +0100, Daniel Thompson wrote: > Currently on ARM when <SysRq-L> is triggered from an interrupt handler > (e.g. a SysRq issued using UART or kbd) the main CPU will wedge for ten > seconds with interrupts masked before issuing a backtrace for every CPU > except itself. > > The new backtrace code introduced by commit 96f0e00378d4 ("ARM: add > basic support for on-demand backtrace of other CPUs") does not work > correctly when run from an interrupt handler because IPI_CPU_BACKTRACE > is used to generate the backtrace on all CPUs but cannot preempt the > current calling context. This patch needs a little more work - what happens to the IPI_CPU_BACKTRACE we've sent to ourselves? (It fires after the interrupt handler for the UART/kbd has finished.) It ought to be masked out if we're going to handle it a different way. -- FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. -- 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/
Powered by blists - more mailing lists