[PATCH 04/11] KVM: arm/arm64: Add kvm_ras.h to collect kvm specific RAS plumbing

James Morse
2018-02-15T18:55:59Z

To split up APEIs in_nmi() path, we need any nmi-like callers to always
be in_nmi(). KVM shouldn't have to know about this, pull the RAS plumbing
out into a header file.

Currently guest synchronous external aborts are claimed as RAS
notifications by handle_guest_sea(), which is hidden in the arch codes
mm/fault.c. 32bit gets a dummy declaration in system_misc.h.

There is going to be more of this in the future if/when we support
the SError-based firmware-first notification mechanism and/or
kernel-first notifications for both synchronous external abort and
SError. Each of these will come with some Kconfig symbols and a
handful of header files.

Create a header file for all this.

This patch gives handle_guest_sea() a 'kvm_' prefix, and moves the
declarations to kvm_ras.h as preparation for a future patch that moves
the ACPI-specific RAS code out of mm/fault.c.

Signed-off-by: James Morse <james.morse@arm.com>
CC: Tyler Baicar <tbaicar@codeaurora.org>
---
arch/arm/include/asm/kvm_ras.h | 14 ++++++++++++++
arch/arm/include/asm/system_misc.h | 5 -----
arch/arm64/include/asm/kvm_ras.h | 11 +++++++++++
arch/arm64/include/asm/system_misc.h | 2 --
arch/arm64/mm/fault.c | 2 +-
virt/kvm/arm/mmu.c | 4 ++--
6 files changed, 28 insertions(+), 10 deletions(-)
create mode 100644 arch/arm/include/asm/kvm_ras.h
create mode 100644 arch/arm64/include/asm/kvm_ras.h

diff --git a/arch/arm/include/asm/kvm_ras.h b/arch/arm/include/asm/kvm_ras.h
new file mode 100644
index 000000000000..aaff56bf338f
--- /dev/null
+++ b/arch/arm/include/asm/kvm_ras.h
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 - Arm Ltd
+
+#ifndef __ARM_KVM_RAS_H__
+#define __ARM_KVM_RAS_H__
+
+#include <linux/types.h>
+
+static inline int kvm_handle_guest_sea(phys_addr_t addr, unsigned int esr)
+{
+ return -1;
+}
+
+#endif /* __ARM_KVM_RAS_H__ */
diff --git a/arch/arm/include/asm/system_misc.h b/arch/arm/include/asm/system_misc.h
index 78f6db114faf..51e5ab50b35f 100644
--- a/arch/arm/include/asm/system_misc.h
+++ b/arch/arm/include/asm/system_misc.h
@@ -23,11 +23,6 @@ extern void (*arm_pm_idle)(void);

extern unsigned int user_debug;

-static inline int handle_guest_sea(phys_addr_t addr, unsigned int esr)
-{
- return -1;
-}
-
#endif /* !__ASSEMBLY__ */

#endif /* __ASM_ARM_SYSTEM_MISC_H */
diff --git a/arch/arm64/include/asm/kvm_ras.h b/arch/arm64/include/asm/kvm_ras.h
new file mode 100644
index 000000000000..5f72b07b7912
--- /dev/null
+++ b/arch/arm64/include/asm/kvm_ras.h
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 - Arm Ltd
+
+#ifndef __ARM64_KVM_RAS_H__
+#define __ARM64_KVM_RAS_H__
+
+#include <linux/types.h>
+
+int kvm_handle_guest_sea(phys_addr_t addr, unsigned int esr);
+
+#endif /* __ARM64_KVM_RAS_H__ */
diff --git a/arch/arm64/include/asm/system_misc.h b/arch/arm64/include/asm/system_misc.h
index 07aa8e3c5630..d0beefeb6d25 100644
--- a/arch/arm64/include/asm/system_misc.h
+++ b/arch/arm64/include/asm/system_misc.h
@@ -56,8 +56,6 @@ extern void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
__show_ratelimited; \
})

-int handle_guest_sea(phys_addr_t addr, unsigned int esr);
-
#endif /* __ASSEMBLY__ */

#endif /* __ASM_SYSTEM_MISC_H */
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index f76bb2c3c943..adac28ce9be3 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -673,7 +673,7 @@ static const struct fault_info fault_info[] = {
{ do_bad, SIGBUS, BUS_FIXME, "unknown 63" },
};

-int handle_guest_sea(phys_addr_t addr, unsigned int esr)
+int kvm_handle_guest_sea(phys_addr_t addr, unsigned int esr)
{
int ret = -ENOENT;

diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index ec62d1cccab7..8ae691194170 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -27,10 +27,10 @@
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_mmio.h>
+#include <asm/kvm_ras.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/virt.h>
-#include <asm/system_misc.h>

#include "trace.h"

@@ -1535,7 +1535,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
* For RAS the host kernel may handle this abort.
* There is no need to pass the error into the guest.
*/
- if (!handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu)))
+ if (!kvm_handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu)))
return 1;

if (unlikely(!is_iabt)) {
--
2.15.1