On Tue, Feb 24, 2015 at 10:33:02AM +0000, Geert Uytterhoeven wrote:

On Mon, Feb 23, 2015 at 5:52 PM, Laurent Pinchart
[off-list ref] wrote:

quoted

On Sunday 22 February 2015 17:09:06 Vincent Stehl? wrote:

quoted

LPAE iommu page table makes sense only for ARM architecture. Add the
corresponding dependency in Kconfig.

This fixes the following runtime warnings on PA-RISC architecture:

I suppose this is caused by the selftest code ?

quoted

  WARNING: at drivers/iommu/io-pgtable-arm.c:413
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted
3.19.0-next-20150222-00002-gc420256 #2 task: 17ca0000 ti: 17ca8000 task.ti:
17ca8000

       YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
  PSW: 00000000000001001111111100001111 Not tainted
  r00-03  0004ff0f 0000001b 104871b0 17ca83c0
  r04-07  00001000 00000000 00000000 00000000
  r08-11  00000000 40001000 1013b36c 17ca8248
  r12-15  00000080 17e712c0 00000000 17c5e100
  r16-19  0000000c 105d8eb0 40001000 ffffffff
  r20-23  00000000 00800020 1048717c 00000000
  r24-27  00001000 00000000 00000009 10774ce0
  r28-31  00000000 00000027 17ca8480 10486d44
  sr00-03  00000000 00000000 00000000 00000000
  sr04-07  00000000 00000000 00000000 00000000

  IASQ: 00000000 00000000 IAOQ: 10486df4 10486df8
   IIR: 03ffe01f    ISR: 00000000  IOR: 17c86e54
   CPU:        0   CR30: 17ca8000 CR31: 00000002
   ORIG_R28: 00000001
   IAOQ[0]: __arm_lpae_unmap+0x144/0x4cc
   IAOQ[1]: __arm_lpae_unmap+0x148/0x4cc
   RP(r2): arm_lpae_unmap+0x34/0x6c
  Backtrace:
   [<104871b0>] arm_lpae_unmap+0x34/0x6c
   [<10127944>] 0x10127944
   [<10168ee0>] do_one_initcall+0x128/0x1dc
   [<101028fc>] 0x101028fc
   [<10161b48>] kernel_init+0x1c/0x118
   [<1015d01c>] end_fault_vector+0x1c/0x24
   [<101762ec>] save_stack_trace+0x28/0x60

Signed-off-by: Vincent Stehl? <redacted>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Will Deacon <redacted>
---


Hi,

This can be seen with e.g. Linux next-20150222 on parisc with allmodconfig.

Best regards,

V.


 drivers/iommu/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index baa0d97..c73fd72 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig

@@ -22,6 +22,7 @@ config IOMMU_IO_PGTABLE

 config IOMMU_IO_PGTABLE_LPAE
      bool "ARMv7/v8 Long Descriptor Format"
+     depends on ARM

How about ARM || COMPILE_TEST ? It can still be useful to compile the module
on other architectures.

COMPILE_TEST is meant for test-compiling drivers or subsystems that are not
useful on all platforms. IMHO COMPILE_TEST kernels are still supposed to boot
without ill effects.

Now, I understand the issue on PA-RISC is with the selftest, not with the actual
IOMMU_IO_PGTABLE_LPAE module? Then IOMMU_IO_PGTABLE_LPAE
can depend on ARM || COMPILE_TEST (|| ARM64, cfr. Laurent's later email).

But the selftest should protect itself against running on non-ARM, either
by making IOMMU_IO_PGTABLE_LPAE_SELFTEST depend on ARM(64)
(without "|| COMPILE_TEST"), or by adding a check to arm_lpae_do_selftests(),
to please all compile-testers.

Perhaps, but actually the issues reported by the self-test are *real* bugs
that I've now got fixes for. They just don't show up on arm platforms
because of different right shift behaviour.

Will