From: Soeren Moch Date: Thu, 6 Jun 2013 00:26:23 +0000 (-0300) Subject: media: dmxdev: remove dvb_ringbuffer_flush() on writer side X-Git-Tag: v3.2.49~55 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2af951daef68fcb1c6cace0543c420a8c26fe756;p=pandora-kernel.git media: dmxdev: remove dvb_ringbuffer_flush() on writer side commit 414abbd2cd4c2618895f02ed3a76ec6647281436 upstream. In dvb_ringbuffer lock-less synchronizationof reader and writer threads is done with separateread and write pointers. Sincedvb_ringbuffer_flush() modifies the read pointer, this function must not be called from the writer thread. This patch removes the dvb_ringbuffer_flush() calls in the dmxdev ringbuffer write functions, this fixes Oopses "Unable to handle kernel paging request" I could observe for the call chaindvb_demux_read ->dvb_dmxdev_buffer_read -> dvb_ringbuffer_read_user -> __copy_to_user (the reader side of the ringbuffer). The flush calls at the write side are not necessary anyway since ringbuffer_flush is also called in dvb_dmxdev_buffer_read() when an error condition is set in the ringbuffer. This patch should also be applied to stable kernels. Signed-off-by: Soeren Moch Reviewed-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings --- Reading git-diff-tree failed