[AMD Official Use Only - General] Hi Tomi, > -----Original Message----- > From: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx> > Sent: Tuesday, March 12, 2024 1:34 AM > To: Sagar, Vishal <vishal.sagar@xxxxxxx>; > laurent.pinchart@xxxxxxxxxxxxxxxx; vkoul@xxxxxxxxxx > Cc: Simek, Michal <michal.simek@xxxxxxx>; dmaengine@xxxxxxxxxxxxxxx; > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > Allagadapa, Varunkumar <varunkumar.allagadapa@xxxxxxx> > Subject: Re: [PATCH v2 1/2] dmaengine: xilinx: dpdma: Fix race condition in > vsync IRQ > > Hi, > > On 28/02/2024 06:21, Vishal Sagar wrote: > > From: Neel Gandhi <neel.gandhi@xxxxxxxxxx> > > > > The vchan_next_desc() function, called from > > xilinx_dpdma_chan_queue_transfer(), must be called with > > virt_dma_chan.lock held. This isn't correctly handled in all code paths, > > resulting in a race condition between the .device_issue_pending() > > handler and the IRQ handler which causes DMA to randomly stop. Fix it by > > taking the lock around xilinx_dpdma_chan_queue_transfer() calls that are > > missing it. > > > > Signed-off-by: Neel Gandhi <neel.gandhi@xxxxxxx> > > Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxx> > > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx> > > Signed-off-by: Vishal Sagar <vishal.sagar@xxxxxxx> > > > > Link: https://lore.kernel.org/all/20220122121407.11467-1- > neel.gandhi@xxxxxxxxxx > > --- > > drivers/dma/xilinx/xilinx_dpdma.c | 10 ++++++++-- > > 1 file changed, 8 insertions(+), 2 deletions(-) > > This fixes a lockdep warning: > > WARNING: CPU: 1 PID: 466 at drivers/dma/xilinx/xilinx_dpdma.c:834 > > Afaics, this issue has been around since the initial commit, in v5.10, > and the fix applies on top of v5.10. I have tested this on v6.2, which > is where the DP support was added to the board I have. > > So I think you can add: > > Fixes: 7cbb0c63de3f ("dmaengine: xilinx: dpdma: Add the Xilinx > DisplayPort DMA engine driver") > > Tomi > <snip> Thanks for going through the patch. I will add this to the commit message and resend v3. I am still waiting for more reviews to happen. Regards Vishal Sagar
