Messages in this thread | | | Subject | Re: [PATCH 4.2 108/110] pinctrl: baytrail: Serialize all register access | From | Ben Hutchings <> | Date | Sun, 08 Nov 2015 09:38:29 +0000 |
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On Fri, 2015-11-06 at 11:19 -0800, Greg Kroah-Hartman wrote: > 4.2-stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Mika Westerberg <mika.westerberg@linux.intel.com> > > commit 39ce8150a079e3ae6ed9abf26d7918a558ef7c19 upstream. > > There is a hardware issue in Intel Baytrail where concurrent GPIO register > access might result reads of 0xffffffff and writes might get dropped > completely. > > Prevent this from happening by taking the serializing lock in all places > where it is possible that more than one thread might be accessing the > hardware concurrently. [...]
While I have no objection to this, I think a complete fix requires adding mmiowb() before each spin_unlock.
Ben.
-- Ben Hutchings 73.46% of all statistics are made up.[unhandled content-type:application/pgp-signature] | |