watchdog/hpwdt: Only claim UNKNOWN NMI if from iLO

JIRA: https://issues.redhat.com/browse/RHEL-104148

Upstream Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

commit dced0b3
Author: Jerry Hoemann <jerry.hoemann@hpe.com>
Date:   Wed Dec 13 14:53:38 2023 -0700

    watchdog/hpwdt: Only claim UNKNOWN NMI if from iLO

    Avoid unnecessary crashes by claiming only NMIs that are due to
    ERROR signalling or generated by the hpwdt hardware device.

    The code does this, but only for iLO5.

    The intent was to preserve legacy, Gen9 and earlier, semantics of
    using hpwdt for error containtment as hardware/firmware would signal
    fatal IO errors as an NMI with the expectation of hpwdt crashing
    the system.  Howerver, these IO errors should be received by hpwdt
    as an NMI_IO_CHECK.  So the test is overly permissive and should
    not be limited to only ilo5.

    We need to enable this protection for future iLOs not matching the
    current PCI IDs.

    Fixes: 62290a5 ("watchdog: hpwdt: Claim NMIs generated by iLO5")
    Signed-off-by: Jerry Hoemann <jerry.hoemann@hpe.com>
    Reviewed-by: Guenter Roeck <linux@roeck-us.net>
    Link: https://lore.kernel.org/r/20231213215340.495734-2-jerry.hoemann@hpe.com
    Signed-off-by: Guenter Roeck <linux@roeck-us.net>
    Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

Signed-off-by: Joseph Szczypek <jszczype@redhat.com>

Author: Joseph Szczypek

drivers/watchdog/hpwdt.c

@@ -178,7 +178,7 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
 		"3. OA Forward Progress Log\n"
 		"4. iLO Event Log";
 
-	if (ilo5 && ulReason == NMI_UNKNOWN && !mynmi)
+	if (ulReason == NMI_UNKNOWN && !mynmi)
 		return NMI_DONE;
 
 	if (ilo5 && !pretimeout && !mynmi)