linux-toradex.git/arch/powerpc/include, branch v3.4.18

powerpc/eeh: Fix crash on converting OF node to edev

2012-10-12T20:38:39+00:00

commit 1e38b7140185e384da216aff66a711df09b5afc9 upstream.

The kernel crash was reported by Alexy. He was testing some feature
with private kernel, in which Alexy added some code in pci_pm_reset()
to read the CSR after writting it. The bug could be reproduced on
Fiber Channel card (Fibre Channel: Emulex Corporation Saturn-X:
LightPulse Fibre Channel Host Adapter (rev 03)) by the following
commands.

	# echo 1 > /sys/devices/pci0004:01/0004:01:00.0/reset
	# rmmod lpfc
	# modprobe lpfc

The history behind the test case is that those additional config
space reading operations in pci_pm_reset() would cause EEH error,
but we didn't detect EEH error until "modprobe lpfc". For the case,
all the PCI devices on PCI bus (0004:01) were removed and added after
PE reset. Then the EEH devices would be figured out again based on
the OF nodes. Unfortunately, there were some child OF nodes under
PCI device (0004:01:00.0), but they didn't have attached PCI_DN since
they're invisible from PCI domain. However, we were still trying to
convert OF node to EEH device without checking on the attached PCI_DN.
Eventually, it caused the kernel crash as follows:

Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc00000000004d888
cpu 0x0: Vector: 300 (Data Access) at [c000000fc797b950]
    pc: c00000000004d888: .eeh_add_device_tree_early+0x78/0x140
    lr: c00000000004d880: .eeh_add_device_tree_early+0x70/0x140
    sp: c000000fc797bbd0
   msr: 8000000000009032
   dar: 30
 dsisr: 40000000
  current = 0xc000000fc78d9f70
  paca    = 0xc00000000edb0000   softe: 0        irq_happened: 0x00
    pid   = 2951, comm = eehd
enter ? for help
[c000000fc797bc50] c00000000004d848 .eeh_add_device_tree_early+0x38/0x140
[c000000fc797bcd0] c00000000004d848 .eeh_add_device_tree_early+0x38/0x140
[c000000fc797bd50] c000000000051b54 .pcibios_add_pci_devices+0x34/0x190
[c000000fc797bde0] c00000000004fb10 .eeh_reset_device+0x100/0x160
[c000000fc797be70] c0000000000502dc .eeh_handle_event+0x19c/0x300
[c000000fc797bf00] c000000000050570 .eeh_event_handler+0x130/0x1a0
[c000000fc797bf90] c000000000020138 .kernel_thread+0x54/0x70

The patch changes of_node_to_eeh_dev() and just returns NULL if the
passed OF node doesn't have attached PCI_DN.

Reported-by: Alexey Kardashevskiy 
Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: Add "memory" attribute for mfmsr()

2012-08-09T15:31:27+00:00

commit b416c9a10baae6a177b4f9ee858b8d309542fbef upstream.

Add "memory" attribute in inline assembly language as a compiler
barrier to make sure 4.6.x GCC don't reorder mfmsr().

Signed-off-by: Tiejun Chen 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: Fix build of some debug irq code

2012-07-16T16:03:49+00:00

commit 21b2de341270bd7bb7a811027ffe63276d9b3b75 upstream.

There was a typo, checking for CONFIG_TRACE_IRQFLAG instead of
CONFIG_TRACE_IRQFLAGS causing some useful debug code to not be
built

This in turns causes a build error on BookE 64-bit due to incorrect
semicolons at the end of a couple of macros, so let's fix that too

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: More fixes for lazy IRQ vs. idle

2012-07-16T16:03:49+00:00

commit be2cf20a5ad31ebb13562c1c866ecc626fbd721e upstream.

Looks like we still have issues with pSeries and Cell idle code
vs. the lazy irq state. In fact, the reset fixes that went upstream
are exposing the problem more by causing BUG_ON() to trigger (which
this patch turns into a WARN_ON instead).

We need to be careful when using a variant of low power state that
has the side effect of turning interrupts back on, to properly set
all the SW & lazy state to look as if everything is enabled before
we enter the low power state with MSR:EE off as we will return with
MSR:EE on. If not, we have a discrepancy of state which can cause
things to go very wrong later on.

This patch moves the logic into a helper and uses it from the
pseries and cell idle code. The power4/970 idle code already got
things right (in assembly even !) so I'm not touching it. The power7
"bare metal" idle code is subtly different and correct. Remains PA6T
and some hypervisor based Cell platforms which have questionable
code in there, but they are mostly dead platforms so I'll fix them
when I manage to get final answers from the respective maintainers
about how the low power state actually works on them.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: check_and_cede_processor() never cedes

2012-07-16T16:03:21+00:00

commit 0b17ba7258db83cd02da560884e053b85de371f2 upstream.

Commit f948501b36c6 ("Make hard_irq_disable() actually hard-disable
interrupts") caused check_and_cede_processor to stop working.
->irq_happened will never be zero right after a hard_irq_disable
so the compiler removes the call to cede_processor completely.

The bug was introduced back in the lazy interrupt handling rework
of 3.4 but was hidden until recently because hard_irq_disable did
nothing.

This issue will eventually appear in 3.4 stable since the
hard_irq_disable fix is marked stable, so mark this one for stable
too.

Signed-off-by: Anton Blanchard 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

Make hard_irq_disable() actually hard-disable interrupts

2012-06-22T18:36:57+00:00

commit f948501b36c6b3d9352ce212a197098a7e958971 upstream.

At present, hard_irq_disable() does nothing on powerpc because of
this code in include/linux/interrupt.h:

    #ifndef hard_irq_disable
    #define hard_irq_disable()      do { } while(0)
    #endif

So we need to make our hard_irq_disable be a macro.  It was previously
a macro until commit 7230c56441 ("powerpc: Rework lazy-interrupt
handling") changed it to a static inline function.

Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Paul Mackerras 
Signed-off-by: Greg Kroah-Hartman 
--
 arch/powerpc/include/asm/hw_irq.h |    3 +++
 1 file changed, 3 insertions(+)

powerpc/kvm: Fix VSID usage in 64-bit "PR" KVM

2012-05-16T13:02:11+00:00

The code forgot to scramble the VSIDs the way we normally do
and was basically using the "proto VSID" directly with the MMU.

This means that in practice, KVM used random VSIDs that could
collide with segments used by other user space programs.

Signed-off-by: Benjamin Herrenschmidt 
[agraf: simplify ppc32 case]
Signed-off-by: Alexander Graf

powerpc/irq: Make alignment & program interrupt behave the same

2012-05-08T23:42:33+00:00

Alignment was the last user of the ENABLE_INTS macro, which we can
now remove. All non-syscall exceptions now disable interrupts on
entry, they get re-enabled conditionally from C code. Don't
unconditionally re-enable in program check either, check the
original context.

Signed-off-by: Benjamin Herrenschmidt

powerpc/irqdomain: Fix broken NR_IRQ references

2012-04-30T00:45:26+00:00

The switch from using irq_map to irq_alloc_desc*() for managing irq
number allocations introduced new bugs in some of the powerpc
interrupt code.  Several functions rely on the value of NR_IRQS to
determine the maximum irq number that could get allocated.  However,
with sparse_irq and using irq_alloc_desc*() the maximum possible irq
number is now specified with 'nr_irqs' which may be a number larger
than NR_IRQS.  This has caused breakage on powermac when
CONFIG_NR_IRQS is set to 32.

This patch removes most of the direct references to NR_IRQS in the
powerpc code and replaces them with either a nr_irqs reference or by
using the common for_each_irq_desc() macro.  The powerpc-specific
for_each_irq() macro is removed at the same time.

Also, the Cell axon_msi driver is refactored to remove the global
build assumption on the size of NR_IRQS and instead add a limit to the
maximum irq number when calling irq_domain_add_nomap().

Signed-off-by: Grant Likely 
Signed-off-by: Benjamin Herrenschmidt

powerpc/mpic: Properly set default triggers

2012-04-23T01:04:30+00:00

This gets rid of the unused default senses array, and replaces the
incorrect use of IRQ_TYPE_NONE with the new IRQ_TYPE_DEFAULT for
the initial set_trigger() call when mapping an interrupt.

This in turn makes us read the HW state and update the irq desc
accordingly.

Signed-off-by: Benjamin Herrenschmidt