UV NMI callback's should not write stack dumps when a kdump is to be written.
When invoking the crash kernel to write a dump, kdump_nmi_shootdown_cpus()
uses NMI's to get all the cpu's to save their register context and halt.
But the NMI interrupt handler runs a callback list. This patch sets a flag
to prevent any of those callbacks from interfering with the halt of the cpu.
For UV, which currently has the only callback to which this is relevant, the
uv_handle_nmi() callback should not do dumping of stacks.
The 'in_crash_kexec' flag is defined as an extern in kdebug.h firstly
because x2apic_uv_x.c includes it. Secondly because some future callback
might need the flag to know that it should not enter the debugger.
(Such a scenario was in fact present in the 2.6.32 kernel, SuSE distribution,
where a call to kdb needed to be avoided.)
Signed-off-by: Cliff Wickman <cpw@sgi.com>
LKML-Reference: <E1ObLvt-0005UZ-Va@eag09.americas.sgi.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This effectively reverts commit 61d047be99.
Disabling the IOMMU can potetially allow DMA transactions to
complete without being translated. Leave it enabled, and allow
crash kernel to do the IOMMU reinitialization properly.
Cc: stable@kernel.org
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch cleans up pci_iommu_shutdown() a bit to use
x86_platform (similar to how IA64 initializes an IOMMU driver).
This adds iommu_shutdown() to x86_platform to avoid calling
every IOMMUs' shutdown functions in pci_iommu_shutdown() in
order. The IOMMU shutdown functions are platform specific (we
don't have multiple different IOMMU hardware) so the current way
is pointless.
An IOMMU driver sets x86_platform.iommu_shutdown to the shutdown
function if necessary.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: joerg.roedel@amd.com
LKML-Reference: <20091027163358F.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If the IOMMUs are still enabled when the kexec kernel boots access to
the disk is not possible. This is bad for tools like kdump or anything
else which wants to use PCI devices.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
We need to disable virtualization extensions on all CPUs before booting
the kdump kernel, otherwise the kdump kernel booting will fail, and
rebooting after the kdump kernel did its task may also fail.
We do it using cpu_emergency_vmxoff() and cpu_emergency_svm_disable(),
that should always work, because those functions check if the CPUs
support SVM or VMX before doing their tasks.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Impact: make nmi_shootdown_cpus() available to the rest of the x86 platform
Now nmi_shootdown_cpus() is ready to be used by non-kdump code also.
Move it to reboot.c.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: make API available to the rest of x86 platform code
Add prototype to asm/reboot.h.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: extend nmi_shootdown_cpus() with a callback
The reboot code will use a different function on crash_nmi_callback().
Adding a function pointer parameter to nmi_shootdown_cpus() for that.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
For the kdump-specific code that was living on nmi_shootdown_cpus().
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
This variable will be moved to non-kdump-specific code.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
The NMI CPU-halting code will be used on non-kdump cases, also
(e.g. emergency_reboot when virtualization is enabled).
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch a llows machine_crash_shutdown to
be replaced, just like any of the other functions
in machine_ops
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
we should also add hpet_disable() for kdump.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Most of contents in crash are same.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
