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Commit Graph

12971 Commits

Author SHA1 Message Date
Justin P. Mattock
0be839bfb4 KVM: Remove base_addresss in kvm_pit since it is unused
The patch below removes unsigned long base_addresss; in i8254.h
since it is unused.

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:03 -04:00
Joerg Roedel
628afd2aeb KVM: SVM: Remove nested sel_cr0_write handling code
This patch removes all the old code which handled the nested
selective cr0 write intercepts. This code was only in place
as a work-around until the instruction emulator is capable
of doing the same. This is the case with this patch-set and
so the code can be removed.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:03 -04:00
Joerg Roedel
f6511935f4 KVM: SVM: Add checks for IO instructions
This patch adds code to check for IOIO intercepts on
instructions decoded by the KVM instruction emulator.

[avi: fix build error due to missing #define D2bvIP]

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:03 -04:00
Joerg Roedel
bf608f88fa KVM: SVM: Add intercept checks for one-byte instructions
This patch add intercept checks for emulated one-byte
instructions to the KVM instruction emulation path.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:02 -04:00
Joerg Roedel
8061252ee0 KVM: SVM: Add intercept checks for remaining twobyte instructions
This patch adds intercepts checks for the remaining twobyte
instructions to the KVM instruction emulator.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:02 -04:00
Joerg Roedel
d7eb820306 KVM: SVM: Add intercept checks for remaining group7 instructions
This patch implements the emulator intercept checks for the
RDTSCP, MONITOR, and MWAIT instructions.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:02 -04:00
Joerg Roedel
01de8b09e6 KVM: SVM: Add intercept checks for SVM instructions
This patch adds the necessary code changes in the
instruction emulator and the extensions to svm.c to
implement intercept checks for the svm instructions.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:02 -04:00
Joerg Roedel
dee6bb70e4 KVM: SVM: Add intercept checks for descriptor table accesses
This patch add intercept checks into the KVM instruction
emulator to check for the 8 instructions that access the
descriptor table addresses.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:02 -04:00
Joerg Roedel
3b88e41a41 KVM: SVM: Add intercept check for accessing dr registers
This patch adds the intercept checks for instruction
accessing the debug registers.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:01 -04:00
Joerg Roedel
cfec82cb7d KVM: SVM: Add intercept check for emulated cr accesses
This patch adds all necessary intercept checks for
instructions that access the crX registers.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:01 -04:00
Joerg Roedel
8a76d7f25f KVM: x86: Add x86 callback for intercept check
This patch adds a callback into kvm_x86_ops so that svm and
vmx code can do intercept checks on emulated instructions.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:01 -04:00
Joerg Roedel
8ea7d6aef8 KVM: x86 emulator: Add flag to check for protected mode instructions
This patch adds a flag for the opcoded to tag instruction
which are only recognized in protected mode. The necessary
check is added too.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:01 -04:00
Joerg Roedel
d09beabd7c KVM: x86 emulator: Add check_perm callback
This patch adds a check_perm callback for each opcode into
the instruction emulator. This will be used to do all
necessary permission checks on instructions before checking
whether they are intercepted or not.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:01 -04:00
Joerg Roedel
775fde8648 KVM: x86 emulator: Don't write-back cpu-state on X86EMUL_INTERCEPTED
This patch prevents the changed CPU state to be written back
when the emulator detected that the instruction was
intercepted by the guest.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:00 -04:00
Avi Kivity
3c6e276f22 KVM: x86 emulator: add SVM intercepts
Add intercept codes for instructions defined by SVM as
interceptable.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:00 -04:00
Avi Kivity
c4f035c60d KVM: x86 emulator: add framework for instruction intercepts
When running in guest mode, certain instructions can be intercepted by
hardware.  This also holds for nested guests running on emulated
virtualization hardware, in particular instructions emulated by kvm
itself.

This patch adds a framework for intercepting instructions.  If an
instruction is marked for interception, and if we're running in guest
mode, a callback is called to check whether an intercept is needed or
not.  The callback is called at three points in time: immediately after
beginning execution, after checking privilge exceptions, and after
checking memory exception.  This suits the different interception points
defined for different instructions and for the various virtualization
instruction sets.

In addition, a new X86EMUL_INTERCEPT is defined, which any callback or
memory access may define, allowing the more complicated intercepts to be
implemented in existing callbacks.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:57:00 -04:00
Avi Kivity
aa97bb4891 KVM: x86 emulator: implement movdqu instruction (f3 0f 6f, f3 0f 7f)
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:59 -04:00
Avi Kivity
1253791df9 KVM: x86 emulator: SSE support
Add support for marking an instruction as SSE, switching registers used
to the SSE register file.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:59 -04:00
Avi Kivity
0d7cdee83a KVM: x86 emulator: Specialize decoding for insns with 66/f2/f3 prefixes
Most SIMD instructions use the 66/f2/f3 prefixes to distinguish between
different variants of the same instruction.  Usually the encoding is quite
regular, but in some cases (including non-SIMD instructions) the prefixes
generate very different instructions.  Examples include XCHG/PAUSE,
MOVQ/MOVDQA/MOVDQU, and MOVBE/CRC32.

Allow the emulator to handle these special cases by splitting such opcodes
into groups, with different decode flags and execution functions for different
prefixes.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:59 -04:00
Avi Kivity
5037f6f324 KVM: x86 emulator: define callbacks for using the guest fpu within the emulator
Needed for emulating fpu instructions.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
1d6b114f20 KVM: x86 emulator: do not munge rep prefix
Currently we store a rep prefix as 1 or 2 depending on whether it is a REPE or
REPNE.  Since sse instructions depend on the prefix value, store it as the
original opcode to simplify things further on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
cef4dea07f KVM: 16-byte mmio support
Since sse instructions can issue 16-byte mmios, we need to support them.  We
can't increase the kvm_run mmio buffer size to 16 bytes without breaking
compatibility, so instead we break the large mmios into two smaller 8-byte
ones.  Since the bus is 64-bit we aren't breaking any atomicity guarantees.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
5287f194bf KVM: Split mmio completion into a function
Make room for sse mmio completions.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
70252a1053 KVM: extend in-kernel mmio to handle >8 byte transactions
Needed for coalesced mmio using sse.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Gleb Natapov
1499e54af0 KVM: x86: better fix for race between nmi injection and enabling nmi window
Fix race between nmi injection and enabling nmi window in a simpler way.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-05-11 07:56:57 -04:00
Marcelo Tosatti
c761e5868e Revert "KVM: Fix race between nmi injection and enabling nmi window"
This reverts commit f86368493e.

Simpler fix to follow.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-05-11 07:56:57 -04:00
Glauber Costa
3291892450 KVM: expose async pf through our standard mechanism
As Avi recently mentioned, the new standard mechanism for exposing features
is KVM_GET_SUPPORTED_CPUID, not spamming CAPs. For some reason async pf
missed that.

So expose async_pf here.

Signed-off-by: Glauber Costa <glommer@redhat.com>
CC: Gleb Natapov <gleb@redhat.com>
CC: Avi Kivity <avi@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:57 -04:00
Avi Kivity
654f06fc65 KVM: VMX: simplify NMI mask management
Use vmx_set_nmi_mask() instead of open-coding management of
the hardware bit and the software hint (nmi_known_unmasked).

There's a slight change of behaviour when running without
hardware virtual NMI support - we now clear the NMI mask if
NMI delivery faulted in that case as well.  This improves
emulation accuracy.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:57 -04:00
Jan Kiszka
89a9fb78b5 KVM: SVM: Remove unused svm_features
We use boot_cpu_has now.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:57 -04:00
Avi Kivity
8878647585 KVM: VMX: Use cached VM_EXIT_INTR_INFO in handle_exception
vmx_complete_atomic_exit() cached it for us, so we can use it here.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
c5ca8e572c KVM: VMX: Don't VMREAD VM_EXIT_INTR_INFO unconditionally
Only read it if we're going to use it later.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
00eba012d5 KVM: VMX: Refactor vmx_complete_atomic_exit()
Move the exit reason checks to the front of the function, for early
exit in the common case.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
f9902069c4 KVM: VMX: Qualify check for host NMI
Check for the exit reason first; this allows us, later,
to avoid a VMREAD for VM_EXIT_INTR_INFO_FIELD.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
9d58b93192 KVM: VMX: Avoid vmx_recover_nmi_blocking() when unneeded
When we haven't injected an interrupt, we don't need to recover
the nmi blocking state (since the guest can't set it by itself).
This allows us to avoid a VMREAD later on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
69c7302890 KVM: VMX: Cache cpl
We may read the cpl quite often in the same vmexit (instruction privilege
check, memory access checks for instruction and operands), so we gain
a bit if we cache the value.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity
f4c63e5d5a KVM: VMX: Optimize vmx_get_cpl()
In long mode, vm86 mode is disallowed, so we need not check for
it.  Reading rflags.vm may require a VMREAD, so it is expensive.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity
6de12732c4 KVM: VMX: Optimize vmx_get_rflags()
If called several times within the same exit, return cached results.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity
f6e7847589 KVM: Use kvm_get_rflags() and kvm_set_rflags() instead of the raw versions
Some rflags bits are owned by the host, not guest, so we need to use
kvm_get_rflags() to strip those bits away or kvm_set_rflags() to add them
back.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Peter Zijlstra
63b6a6758e perf events, x86: Fix Intel Nehalem and Westmere last level cache event definitions
The Intel Nehalem offcore bits implemented in:

  e994d7d23a: perf: Fix LLC-* events on Intel Nehalem/Westmere

... are wrong: they implemented _ACCESS as _HIT and counted OTHER_CORE_HIT* as
MISS even though its clearly documented as an L3 hit ...

Fix them and the Westmere definitions as well.

Cc: Andi Kleen <ak@linux.intel.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1299119690-13991-3-git-send-email-ming.m.lin@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-06 11:24:48 +02:00
Ingo Molnar
4d70230bb4 Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into perf/urgent 2011-05-06 08:11:28 +02:00
Ingo Molnar
98bb318864 Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent 2011-05-04 20:33:42 +02:00
Linus Torvalds
609cfda586 Merge branch 'stable/bug-fixes-for-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug-fixes-for-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: mask_rw_pte mark RO all pagetable pages up to pgt_buf_top
  xen/mmu: Add workaround "x86-64, mm: Put early page table high"
2011-05-03 09:25:42 -07:00
H. Peter Anvin
7806a49ab6 x86, reboot: Fix relocations in reboot_32.S
The use of base for %ebx in this file is arbitrary, *except* that we
also use it to compute the real-mode segment.  Therefore, make it so
that r_base really is the true address to which %ebx points.

This resolves kernel bugzilla 33302.

Reported-and-tested-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-08os5wi3yq1no0y4i5m4z7he@git.kernel.org
2011-05-02 14:44:46 -07:00
Stefano Stabellini
b9269dc7bf xen: mask_rw_pte mark RO all pagetable pages up to pgt_buf_top
mask_rw_pte is currently checking if a pfn is a pagetable page if it
falls in the range pgt_buf_start - pgt_buf_end but that is incorrect
because pgt_buf_end is a moving target: pgt_buf_top is the real
boundary.

Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02 16:33:52 -04:00
Konrad Rzeszutek Wilk
a38647837a xen/mmu: Add workaround "x86-64, mm: Put early page table high"
As a consequence of the commit:

commit 4b239f458c
Author: Yinghai Lu <yinghai@kernel.org>
Date:   Fri Dec 17 16:58:28 2010 -0800

    x86-64, mm: Put early page table high

it causes the Linux kernel to crash under Xen:

mapping kernel into physical memory
Xen: setup ISA identity maps
about to get started...
(XEN) mm.c:2466:d0 Bad type (saw 7400000000000001 != exp 1000000000000000) for mfn b1d89 (pfn bacf7)
(XEN) mm.c:3027:d0 Error while pinning mfn b1d89
(XEN) traps.c:481:d0 Unhandled invalid opcode fault/trap [#6] on VCPU 0 [ec=0000]
(XEN) domain_crash_sync called from entry.S
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
...

The reason is that at some point init_memory_mapping is going to reach
the pagetable pages area and map those pages too (mapping them as normal
memory that falls in the range of addresses passed to init_memory_mapping
as argument). Some of those pages are already pagetable pages (they are
in the range pgt_buf_start-pgt_buf_end) therefore they are going to be
mapped RO and everything is fine.
Some of these pages are not pagetable pages yet (they fall in the range
pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they
are going to be mapped RW.  When these pages become pagetable pages and
are hooked into the pagetable, xen will find that the guest has already
a RW mapping of them somewhere and fail the operation.
The reason Xen requires pagetables to be RO is that the hypervisor needs
to verify that the pagetables are valid before using them. The validation
operations are called "pinning" (more details in arch/x86/xen/mmu.c).

In order to fix the issue we mark all the pages in the entire range
pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation
is completed only the range pgt_buf_start-pgt_buf_end is reserved by
init_memory_mapping. Hence the kernel is going to crash as soon as one
of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those
ranges are RO).

For this reason, this function is introduced which is called _after_
the init_memory_mapping has completed (in a perfect world we would
call this function from init_memory_mapping, but lets ignore that).

Because we are called _after_ init_memory_mapping the pgt_buf_[start,
end,top] have all changed to new values (b/c another init_memory_mapping
is called). Hence, the first time we enter this function, we save
away the pgt_buf_start value and update the pgt_buf_[end,top].

When we detect that the "old" pgt_buf_start through pgt_buf_end
PFNs have been reserved (so memblock_x86_reserve_range has been called),
we immediately set out to RW the "old" pgt_buf_end through pgt_buf_top.

And then we update those "old" pgt_buf_[end|top] with the new ones
so that we can redo this on the next pagetable.

Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[v1: Updated with Jeremy's comments]
[v2: Added the crash output]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02 16:33:34 -04:00
Yinghai Lu
2be19102b7 x86, NUMA: Fix empty memblk detection in numa_cleanup_meminfo()
numa_cleanup_meminfo() trims each memblk between low (0) and
high (max_pfn) limits and discards empty ones.  However, the
emptiness detection incorrectly used equality test.  If the
start of a memblk is higher than max_pfn, it is empty but fails
the equality test and doesn't get discarded.

The condition triggers when max_pfn is lower than start of a
NUMA node and results in memory misconfiguration - leading to
WARN_ON()s and other funnies.  The bug was discovered in devel
branch where 32bit too uses this code path for NUMA init.  If a
node is above the addressing limit, max_pfn ends up lower than
the node triggering this problem.

The failure hasn't been observed on x86-64 but is still possible
with broken hardware e820/NUMA info.  As the fix is very low
risk, it would be better to apply it even for 64bit.

Fix it by using >= instead of ==.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Extracted the actual fix from the original patch and rewrote patch description. ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110501171204.GO29280@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-01 19:15:11 +02:00
Boris Ostrovsky
e20a2d205c x86, AMD: Fix APIC timer erratum 400 affecting K8 Rev.A-E processors
Older AMD K8 processors (Revisions A-E) are affected by erratum
400 (APIC timer interrupts don't occur in C states greater than
C1). This, for example, means that X86_FEATURE_ARAT flag should
not be set for these parts.

This addresses regression introduced by commit
b87cf80af3 ("x86, AMD: Set ARAT
feature on AMD processors") where the system may become
unresponsive until external interrupt (such as keyboard input)
occurs. This results, for example, in time not being reported
correctly, lack of progress on the system and other lockups.

Reported-by: Joerg-Volker Peetz <jvpeetz@web.de>
Tested-by: Joerg-Volker Peetz <jvpeetz@web.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Boris Ostrovsky <Boris.Ostrovsky@amd.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1304113663-6586-1-git-send-email-ostr@amd64.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-01 18:55:51 +02:00
Linus Torvalds
40a963502c Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86, nmi: Move LVT un-masking into irq handlers
  perf events, x86: Work around the Nehalem AAJ80 erratum
  perf, x86: Fix BTS condition
  ftrace: Build without frame pointers on Microblaze
2011-04-29 15:08:53 -07:00
Sebastian Andrzej Siewior
1ff42c32c7 x86: ce4100: Configure IOAPIC pins for USB and SATA to level type
The USB and SATA ioapic interrrupt pins are configured as edge type,
but need to be level type interrupts to work correctly.

[ tglx: Split out from the combo patch ]

Cc: Torben Hohn <torbenh@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/%3C20110427143052.GA15211%40linutronix.de%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-04-28 11:38:30 +02:00
Sebastian Andrzej Siewior
20443598d9 x86: devicetree: Configure IOAPIC pin only once
We use io_apic_setup_irq_pin() in order to configure pin's interrupt
number polarity and type. This is done on every irq_create_of_mapping()
which happens for instance during pci enable calls. Level typed
interrupts are masked by default, edge are unmasked.

On the first ->xlate() call the level interrupt is configured and
masked. The driver calls request_irq() and the line is unmasked. Lets
assume the interrupt line is shared with another device and we call
pci_enable_device() for this device. The ->xlate() configures the pin
again and it is masked. request_irq() does not unmask the line because
it _is_ already unmasked according to its internal state. So the
interrupt will never be unmasked again.

This patch is based on an earlier work by Torben Hohn and solves the
problem by configuring the pin only once. Since all devices must agree
on the same type and polarity there is no point in configuring the pin
more than once.

[ tglx: Split out the ce4100 part into a separate patch ]

Cc: Torben Hohn <torbenh@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/%3C20110427143052.GA15211%40linutronix.de%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-04-28 11:38:30 +02:00