hi > >-----Original Message----- >From: Dmitry Baryshkov <[email protected]> >Sent: Wednesday, January 8, 2025 6:43 PM >To: Hermes Wu (吳佳宏) <[email protected]> >Cc: Andrzej Hajda <[email protected]>; Neil Armstrong ><[email protected]>; Robert Foss <[email protected]>; Laurent Pinchart ><[email protected]>; Jonas Karlman <[email protected]>; Jernej >Skrabec <[email protected]>; Maarten Lankhorst ><[email protected]>; Maxime Ripard <[email protected]>; >Thomas Zimmermann <[email protected]>; David Airlie <[email protected]>; >Simona Vetter <[email protected]>; AngeloGioacchino Del Regno ><[email protected]>; [email protected]; >[email protected]; Pet Weng (翁玉芬) <[email protected]>; Kenneth >Hung (洪家倫) <[email protected]>; [email protected] >Subject: Re: [PATCH] drm/bridge: it6505: fix HDCP V match check is not >performed correctly > >On Wed, Jan 08, 2025 at 01:45:14PM +0800, Hermes Wu via B4 Relay wrote: >> From: Hermes Wu <[email protected]> >> >> The loop of V compare is expected to iterate for 5 times which compare >> V array form av[0][] to av[4][]. >> It should check loop counter reach the last statement before return >> true >> >> Fixes: 0989c02c7a5c ("drm/bridge: it6505: fix HDCP CTS compare V >> matching") >> >> Signed-off-by: Hermes Wu <[email protected]> > >No empty lines between tags, please. > >> --- >> drivers/gpu/drm/bridge/ite-it6505.c | 9 ++++++--- >> 1 file changed, 6 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c >> b/drivers/gpu/drm/bridge/ite-it6505.c >> index >> 88ef76a37fe6accacdd343839ff2569b31b18ceb..e87247aea1d2ffbdad192e241056 >> d34fdfb32163 100644 >> --- a/drivers/gpu/drm/bridge/ite-it6505.c >> +++ b/drivers/gpu/drm/bridge/ite-it6505.c >> @@ -2254,9 +2254,12 @@ static bool it6505_hdcp_part2_ksvlist_check(struct >> it6505 *it6505) >> if (bv[i][3] != av[i][0] || bv[i][2] != av[i][1] || >> av[i][1] != av[i][2] || bv[i][0] != av[i][3]) >> break; >> - >> - DRM_DEV_DEBUG_DRIVER(dev, "V' all match!! %d, %d", >> retry, i); >> - return true; >> + if (i == 4) { > >I think there was a similar patch yesteday.
I can't find patch for it6505, would you provide link? If it also fixes this bug, should I just drop this patch? >Anyway, I have exactly the same feedback: please pull this out of the loop, >this is how it's usually checked / done. > I will move it out the loop, Thanks. >> + DRM_DEV_DEBUG_DRIVER(dev, >> + "V' all match!! %d", >> + retry); >> + return true; >> + } >> } >> } >> >> >> --- >> base-commit: 938fbb16aba8f7b88e0fdcf56f315a5bbad41aad >> change-id: 20250107-fix-hdcp-v-comp-3ba8e3d7adf3 >> >> Best regards, >> -- >> Hermes Wu <[email protected]> >> >> > >-- >With best wishes >Dmitry > BR, Hermes
