| Message ID | 1416585613-2113-3-git-send-email-thomas.petazzoni@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Nov 21, 2014 at 04:59:59PM +0100, Thomas Petazzoni wrote: > From: Nadav Haklai <nadavh@marvell.com> > > 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 <linux@arm.linux.org.uk> > Cc: <stable@vger.kernel.org> # v3.8+ > Fixes: de4901933f6d ("arm: mm: Add support for PJ4B cpu and init routines") > Signed-off-by: Nadav Haklai <nadavh@marvell.com> > Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> > Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com> > --- > 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 <thomas.petazzoni@free-electrons.com> > --- > arch/arm/mm/proc-v7.S | 2 -- > 1 file changed, 2 deletions(-) Acked-by: Jason Cooper <jason@lakedaemon.net> Please add to Russell's patch tracker. thx, Jason.
Dear Jason Cooper, On Fri, 21 Nov 2014 19:53:38 -0500, Jason Cooper wrote: > > arch/arm/mm/proc-v7.S | 2 -- > > 1 file changed, 2 deletions(-) > > Acked-by: Jason Cooper <jason@lakedaemon.net> > > Please add to Russell's patch tracker. Thanks, done in http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8222/1. Thomas
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index b3a9478..22ac2a6 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -270,7 +270,6 @@ __v7_pj4b_setup: /* Auxiliary Debug Modes Control 1 Register */ #define PJ4B_STATIC_BP (1 << 2) /* Enable Static BP */ #define PJ4B_INTER_PARITY (1 << 8) /* Disable Internal Parity Handling */ -#define PJ4B_BCK_OFF_STREX (1 << 5) /* Enable the back off of STREX instr */ #define PJ4B_CLEAN_LINE (1 << 16) /* Disable data transfer for clean line */ /* Auxiliary Debug Modes Control 2 Register */ @@ -293,7 +292,6 @@ __v7_pj4b_setup: /* Auxiliary Debug Modes Control 1 Register */ mrc p15, 1, r0, c15, c1, 1 orr r0, r0, #PJ4B_CLEAN_LINE - orr r0, r0, #PJ4B_BCK_OFF_STREX orr r0, r0, #PJ4B_INTER_PARITY bic r0, r0, #PJ4B_STATIC_BP mcr p15, 1, r0, c15, c1, 1