Merge branch 'acpi-apei'

* acpi-apei: (29 commits)
  efi: cper: Fix possible out-of-bounds access
  ACPI: APEI: Fix possible out-of-bounds access to BERT region
  MAINTAINERS: Add James Morse to the list of APEI reviewers
  ACPI / APEI: Add support for the SDEI GHES Notification type
  firmware: arm_sdei: Add ACPI GHES registration helper
  ACPI / APEI: Use separate fixmap pages for arm64 NMI-like notifications
  ACPI / APEI: Only use queued estatus entry during in_nmi_queue_one_entry()
  ACPI / APEI: Split ghes_read_estatus() to allow a peek at the CPER length
  ACPI / APEI: Make GHES estatus header validation more user friendly
  ACPI / APEI: Pass ghes and estatus separately to avoid a later copy
  ACPI / APEI: Let the notification helper specify the fixmap slot
  ACPI / APEI: Move locking to the notification helper
  arm64: KVM/mm: Move SEA handling behind a single 'claim' interface
  KVM: arm/arm64: Add kvm_ras.h to collect kvm specific RAS plumbing
  ACPI / APEI: Switch NOTIFY_SEA to use the estatus queue
  ACPI / APEI: Move NOTIFY_SEA between the estatus-queue and NOTIFY_NMI
  ACPI / APEI: Don't allow ghes_ack_error() to mask earlier errors
  ACPI / APEI: Generalise the estatus queue's notify code
  ACPI / APEI: Don't update struct ghes' flags in read/clear estatus
  ACPI / APEI: Remove spurious GHES_TO_CLEAR check
  ...

1 files changed, 31 insertions, 0 deletions

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 44e3c351e1ea..803f0494dd3e 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -27,8 +27,10 @@
 #include <linux/smp.h>
 #include <linux/serial_core.h>
 
+#include <acpi/ghes.h>
 #include <asm/cputype.h>
 #include <asm/cpu_ops.h>
+#include <asm/daifflags.h>
 #include <asm/pgtable.h>
 #include <asm/smp_plat.h>
 
@@ -256,3 +258,32 @@ pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
 		return __pgprot(PROT_NORMAL_NC);
 	return __pgprot(PROT_DEVICE_nGnRnE);
 }
+
+/*
+ * Claim Synchronous External Aborts as a firmware first notification.
+ *
+ * Used by KVM and the arch do_sea handler.
+ * @regs may be NULL when called from process context.
+ */
+int apei_claim_sea(struct pt_regs *regs)
+{
+	int err = -ENOENT;
+	unsigned long current_flags;
+
+	if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
+		return err;
+
+	current_flags = arch_local_save_flags();
+
+	/*
+	 * SEA can interrupt SError, mask it and describe this as an NMI so
+	 * that APEI defers the handling.
+	 */
+	local_daif_restore(DAIF_ERRCTX);
+	nmi_enter();
+	err = ghes_notify_sea();
+	nmi_exit();
+	local_daif_restore(current_flags);
+
+	return err;
+}