Hi Rafael,

On 11/02/2019 11:05, Rafael J. Wysocki wrote:

On Fri, Feb 8, 2019 at 3:13 PM James Morse [off-list ref] wrote:

quoted

On 08/02/2019 11:40, Rafael J. Wysocki wrote:

quoted

On Tuesday, January 29, 2019 7:48:36 PM CET James Morse wrote:

quoted

This series aims to wire-up arm64's fancy new software-NMI notifications
for firmware-first RAS. These need to use the estatus-queue, which is
also needed for notifications via emulated-SError. All of these
things take the 'in_nmi()' path through ghes_copy_tofrom_phys(), and
so will deadlock if they can interact, which they might.

quoted

quoted

Known issues:
 * ghes_copy_tofrom_phys() already takes a lock in NMI context, this
   series moves that around, and makes sure we never try to take the
   same lock from different NMIlike notifications. Since the switch to
   queued spinlocks it looks like the kernel can only be 4 context's
   deep in spinlock, which arm64 could exceed as it doesn't have a
   single architected NMI. This would be fixed by dropping back to
   test-and-set when the nesting gets too deep:
 lore.kernel.org/r/1548215351-18896-1-git-send-email-longman@redhat.com

* Taking an NMI from a KVM guest on arm64 with VHE leaves HCR_EL2.TGE
  clear, meaning AT and TLBI point at the guest, and PAN/UAO are squiffy.
  Only TLBI matters for APEI, and this is fixed by Julien's patch:
 http://lore.kernel.org/r/1548084825-8803-2-git-send-email-julien.thierry@arm.com (local)

* Linux ignores the physical address mask, meaning it doesn't call
  memory_failure() on all the affected pages if firmware or hypervisor
  believe in a different page size. Easy to hit on arm64, (easy to fix too,
  it just conflicts with this series)

quoted

quoted

James Morse (26):
  ACPI / APEI: Don't wait to serialise with oops messages when
    panic()ing
  ACPI / APEI: Remove silent flag from ghes_read_estatus()
  ACPI / APEI: Switch estatus pool to use vmalloc memory
  ACPI / APEI: Make hest.c manage the estatus memory pool
  ACPI / APEI: Make estatus pool allocation a static size
  ACPI / APEI: Don't store CPER records physical address in struct ghes
  ACPI / APEI: Remove spurious GHES_TO_CLEAR check
  ACPI / APEI: Don't update struct ghes' flags in read/clear estatus
  ACPI / APEI: Generalise the estatus queue's notify code
  ACPI / APEI: Don't allow ghes_ack_error() to mask earlier errors
  ACPI / APEI: Move NOTIFY_SEA between the estatus-queue and NOTIFY_NMI
  ACPI / APEI: Switch NOTIFY_SEA to use the estatus queue
  KVM: arm/arm64: Add kvm_ras.h to collect kvm specific RAS plumbing
  arm64: KVM/mm: Move SEA handling behind a single 'claim' interface
  ACPI / APEI: Move locking to the notification helper
  ACPI / APEI: Let the notification helper specify the fixmap slot
  ACPI / APEI: Pass ghes and estatus separately to avoid a later copy
  ACPI / APEI: Make GHES estatus header validation more user friendly
  ACPI / APEI: Split ghes_read_estatus() to allow a peek at the CPER
    length
  ACPI / APEI: Only use queued estatus entry during
    in_nmi_queue_one_entry()
  ACPI / APEI: Use separate fixmap pages for arm64 NMI-like
    notifications
  mm/memory-failure: Add memory_failure_queue_kick()
  ACPI / APEI: Kick the memory_failure() queue for synchronous errors
  arm64: acpi: Make apei_claim_sea() synchronise with APEI's irq work
  firmware: arm_sdei: Add ACPI GHES registration helper
  ACPI / APEI: Add support for the SDEI GHES Notification type

quoted

I can apply patches in this series up to and including patch [21/26].

Do you want me to do that?

9-12, 17-19, 21 are missing any review/ack tags, so I wouldn't ask, but as
you're offering, yes please!

quoted

Patch [22/26] requires an ACK from mm people.

Patch [23/26] has a problem that randconfig can generate a configuration
in which memory_failure_queue_kick() is not present, so it is necessary
to add a CONFIG_MEMORY_FAILURE dependency somewhere for things to
work (or define an empty stub for that function in case the symbol is
not set).

Damn-it! Thanks, I was just trying to work that report out...

quoted

If patches [24-26/26] don't depend on the previous two, I can try to
apply them either, so please let me know.

22-24 depend on each other. Merging 24 without the other two is no-improvement,
so I'd like them to be kept together.

25-26 don't depend on 22-24, but came later so that they weren't affected by the
same race.
(note to self: describe that in the cover letter next time.)


If I apply the tag's and Boris' changes and post a tested v9 as 1-21, 25-26, is
that easier, or does it cause extra work?

Actually, I went ahead and applied them, since I had the 1-21 ready anyway.

I applied the Boris' fixups manually which led to a bit of rebasing,
so please check my linux-next branch.

Looks okay to me, and I ran your branch through the POLL/SEA/SDEI tests I've
been doing for each version so far.


Thanks!

James

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel