linux-toradex.git/arch/x86/kernel/crash.c, branch v3.0.44

x86, UV: Make kdump avoid stack dumps

2010-07-21T18:33:27+00:00

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 
LKML-Reference: 
Signed-off-by: H. Peter Anvin

Revert "x86: disable IOMMUs on kernel crash"

2010-04-07T09:51:17+00:00

This effectively reverts commit 61d047be99757fd9b0af900d7abce9a13a337488.

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 
Cc: Eric Biederman 
Cc: Neil Horman 
Cc: Vivek Goyal 
Signed-off-by: Chris Wright 
Signed-off-by: Joerg Roedel

x86: Use x86_platform for iommu_shutdown

2009-11-08T12:12:26+00:00

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 
Cc: joerg.roedel@amd.com
LKML-Reference: <20091027163358F.fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar

x86: disable IOMMUs on kernel crash

2009-06-15T13:20:40+00:00

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

x86, apic: remove duplicate asm/apic.h inclusions

2009-02-17T16:52:44+00:00

Impact: cleanup

Signed-off-by: Ingo Molnar

x86, apic: remove genapic.h

2009-02-17T16:52:44+00:00

Impact: cleanup

Remove genapic.h and remove all references to it.

Signed-off-by: Ingo Molnar

x86, smp: remove mach_ipi.h

2009-01-29T13:16:49+00:00

Move mach_ipi.h definitions into genapic.h.

Signed-off-by: Ingo Molnar

x86: smp.h move safe_smp_processor_id declartion to cpu.h

2009-01-07T20:48:25+00:00

Impact: cleanup

Signed-off-by: Jaswinder Singh Rajput 
Signed-off-by: Ingo Molnar

kdump: forcibly disable VMX and SVM on machine_crash_shutdown()

2008-12-31T14:52:30+00:00

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 
Signed-off-by: Avi Kivity

x86: move nmi_shootdown_cpus() to reboot.c

2008-11-12T17:55:47+00:00

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 
Signed-off-by: Ingo Molnar