From mboxrd@z Thu Jan 1 00:00:00 1970 From: lauraa@codeaurora.org (Laura Abbott) Date: Thu, 11 Oct 2012 17:52:26 -0700 Subject: [PATCH 2/2] ARM: unwind: enable dumping stacks for SMP && ARM_UNWIND In-Reply-To: <1346021216-21979-3-git-send-email-ccross@android.com> References: <1346021216-21979-1-git-send-email-ccross@android.com> <1346021216-21979-3-git-send-email-ccross@android.com> Message-ID: <507769CA.6090903@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, On 8/26/2012 3:46 PM, Colin Cross wrote: > Unwinding with CONFIG_ARM_UNWIND is much more complicated than > unwinding with CONFIG_FRAME_POINTER, but there are only a few points > that require validation in order to avoid faults or infinite loops. > Avoiding faults is easy by adding checks to verify that all accesses > relative to the frame's stack pointer remain inside the stack. > > When CONFIG_FRAME_POINTER is not set it is possible for two frames to > have the same SP, so there is no way to avoid repeated calls to > unwind_frame continuing forever. > > Signed-off-by: Colin Cross > --- This is a feature we've wanted for a long time. I ran some test with repeated catting of stacks with processes dying and the results looked good. You can add a Tested-by: Laura Abbott Laura -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation