Hi Rafael, On 11/02/2019 11:05, Rafael J. Wysocki wrote: > On Fri, Feb 8, 2019 at 3:13 PM James Morse <james.morse at arm.com> wrote: >> On 08/02/2019 11:40, Rafael J. Wysocki wrote: >>> On Tuesday, January 29, 2019 7:48:36 PM CET James Morse wrote: >>>> 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. >> >>>> 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 at 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 at arm.com >>>> >>>> * 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) >> >> >>>> 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 >> >> >>> 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! >> >> >>> 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... >> >> >>> 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
