[PATCH 3/3] watchdog: hpwdt: Check source of NMI

From: Jerry Hoemann
Date: Fri Oct 20 2017 - 19:04:55 EST


Do not claim the NMI (i.e. return NMI_DONE) if the source of
the NMI isn't the iLO watchdog or debug.

Signed-off-by: Jerry Hoemann <jerry.hoemann@xxxxxxx>
---
drivers/watchdog/hpwdt.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
index 4c011e8..b64ce43 100644
--- a/drivers/watchdog/hpwdt.c
+++ b/drivers/watchdog/hpwdt.c
@@ -53,6 +53,7 @@
static const int pretimeout = 9;

static void __iomem *pci_mem_addr; /* the PCI-memory address */
+static unsigned long __iomem *hpwdt_nmistat;
static unsigned long __iomem *hpwdt_timer_reg;
static unsigned long __iomem *hpwdt_timer_con;

@@ -475,6 +476,11 @@ static int hpwdt_time_left(void)
return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
}

+static int hpwdt_my_nmi(void)
+{
+ return ioread8(hpwdt_nmistat) & 0x6;
+}
+
#ifdef CONFIG_HPWDT_NMI_DECODING
/*
* NMI Handler
@@ -487,6 +493,9 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
if (!hpwdt_nmi_decoding)
return NMI_DONE;

+ if ((ulReason == NMI_UNKNOWN) && !hpwdt_my_nmi())
+ return NMI_DONE;
+
spin_lock_irqsave(&rom_lock, rom_pl);
if (!die_nmi_called && !is_icru && !is_uefi)
asminline_call(&cmn_regs, cru_rom_addr);
@@ -849,6 +858,7 @@ static int hpwdt_init_one(struct pci_dev *dev,
retval = -ENOMEM;
goto error_pci_iomap;
}
+ hpwdt_nmistat = pci_mem_addr + 0x6e;
hpwdt_timer_reg = pci_mem_addr + 0x70;
hpwdt_timer_con = pci_mem_addr + 0x72;

--
1.8.3.1