[PATCH 4.8 76/85] watchdog: qcom: fix kernel panic due to external abort on non-linefetch

From: Greg Kroah-Hartman
Date: Wed Jan 04 2017 - 15:58:04 EST


4.8-stable review patch. If anyone has any objections, please let me know.

------------------

From: Christian Lamparter <chunkeey@xxxxxxxxxxxxxx>

commit f06f35c66fdbd5ac38901a3305ce763a0cd59375 upstream.

This patch fixes a off-by-one in the "watchdog: qcom: add option for
standalone watchdog not in timer block" patch that causes the
following panic on boot:

> Unhandled fault: external abort on non-linefetch (0x1008) at 0xc8874002
> pgd = c0204000
> [c8874002] *pgd=87806811, *pte=0b017653, *ppte=0b017453
> Internal error: : 1008 [#1] SMP ARM
> CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.8.6 #0
> Hardware name: Generic DT based system
> PC is at 0xc02222f4
> LR is at 0x1
> pc : [<c02222f4>] lr : [<00000001>] psr: 00000113
> sp : c782fc98 ip : 00000003 fp : 00000000
> r10: 00000004 r9 : c782e000 r8 : c04ab98c
> r7 : 00000001 r6 : c8874002 r5 : c782fe00 r4 : 00000002
> r3 : 00000000 r2 : c782fe00 r1 : 00100000 r0 : c8874002
> Flags: nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
> Control: 10c5387d Table: 8020406a DAC: 00000051
> Process swapper/0 (pid: 1, stack limit = 0xc782e210)
> Stack: (0xc782fc98 to 0xc7830000)
> [...]

The WDT_STS (status) needs to be translated via wdt_addr as well.

fixes: f0d9d0f4b44a ("watchdog: qcom: add option for standalone watchdog not in timer block")
Signed-off-by: Christian Lamparter <chunkeey@xxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/watchdog/qcom-wdt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/watchdog/qcom-wdt.c
+++ b/drivers/watchdog/qcom-wdt.c
@@ -209,7 +209,7 @@ static int qcom_wdt_probe(struct platfor
wdt->wdd.parent = &pdev->dev;
wdt->layout = regs;

- if (readl(wdt->base + WDT_STS) & 1)
+ if (readl(wdt_addr(wdt, WDT_STS)) & 1)
wdt->wdd.bootstatus = WDIOF_CARDRESET;

/*