From mboxrd@z Thu Jan 1 00:00:00 1970 From: jason@lakedaemon.net (Jason Cooper) Date: Fri, 21 Nov 2014 19:53:38 -0500 Subject: [PATCHv3 02/16] ARM: mvebu: enable strex backoff delay In-Reply-To: <1416585613-2113-3-git-send-email-thomas.petazzoni@free-electrons.com> References: <1416585613-2113-1-git-send-email-thomas.petazzoni@free-electrons.com> <1416585613-2113-3-git-send-email-thomas.petazzoni@free-electrons.com> Message-ID: <20141122005337.GL22670@titan.lakedaemon.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Nov 21, 2014 at 04:59:59PM +0100, Thomas Petazzoni wrote: > From: Nadav Haklai > > Under extremely rare conditions, in an MPCore node consisting of at > least 3 CPUs, two CPUs trying to perform a STREX to data on the same > shared cache line can enter a livelock situation. > > This patch enables the HW mechanism that overcomes the bug. This fixes > the incorrect setup of the STREX backoff delay bit due to a wrong > description in the specification. > > Note that enabling the STREX backoff delay mechanism is done by > leaving the bit *cleared*, while the bit was currently being set by > the proc-v7.S code. > > [Thomas: adapt to latest mainline, slightly reword the commit log, add > stable markers.] > > Cc: Russell King > Cc: # v3.8+ > Fixes: de4901933f6d ("arm: mm: Add support for PJ4B cpu and init routines") > Signed-off-by: Nadav Haklai > Signed-off-by: Thomas Petazzoni > Acked-by: Gregory CLEMENT > --- > This patch is submitted as part of the suspend/resume work, because > the suspend/resume path is triggering this rare bug in a very > reproducible fashion. > > Signed-off-by: Thomas Petazzoni > --- > arch/arm/mm/proc-v7.S | 2 -- > 1 file changed, 2 deletions(-) Acked-by: Jason Cooper Please add to Russell's patch tracker. thx, Jason.