Re: [PATCH v2 2/3] watchdog: hpwdt: Check source of NMI

[Guenter Roeck]

On 10/23/2017 03:46 PM, Jerry Hoemann wrote:

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.hoem...@hpe.com>

Reviewed-by: Guenter Roeck <li...@roeck-us.net>

---
  drivers/watchdog/hpwdt.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
index 9fd869f..e616583 100644
--- a/drivers/watchdog/hpwdt.c
+++ b/drivers/watchdog/hpwdt.c
@@ -52,6 +52,7 @@
  static unsigned long hpwdt_is_open;

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;

@@ -474,6 +475,11 @@ 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
@@ -486,6 +492,9 @@ 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);
@@ -842,6 +851,7 @@ 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;