[PATCH v3 1/2] acpi: apei: remove the unused dead-code for SEA notification type

From: Dongjiu Geng
Date: Thu Sep 28 2017 - 08:19:36 EST


In current code logic, the two functions ghes_sea_add() and
ghes_sea_remove() are only called when CONFIG_ACPI_APEI_SEA
is defined. If not, it will return errors in the ghes_probe()
and not continue. If the probe is failed, the ghes_sea_remove()
also has no chance to be called. Hence, remove the unnecessary
handling when CONFIG_ACPI_APEI_SEA is not defined.

In the firmware-first RAS solution, the IPA fault address recorded
by hpfar_el2 may be UNKNOWN, and also current code does not use it,
so remove it.

Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
Cc: James Morse <james.morse@xxxxxxx>
Cc: Tyler Baicar <tbaicar@xxxxxxxxxxxxxx>
Signed-off-by: Dongjiu Geng <gengdongjiu@xxxxxxxxxx>

---
v2->v3:
1. remove the fault_ipa address
If ESR_ELx.DFSC is Synchronous External Abort on memory access(0b010000),
the hpfar_el2's value will be UNKNOWN, so this value is not accurate.

It is ever discussed here:
https://lkml.org/lkml/2017/9/8/623
---
arch/arm/include/asm/system_misc.h | 2 +-
arch/arm64/include/asm/system_misc.h | 2 +-
arch/arm64/mm/fault.c | 2 +-
drivers/acpi/apei/ghes.c | 14 --------------
virt/kvm/arm/mmu.c | 2 +-
5 files changed, 4 insertions(+), 18 deletions(-)

diff --git a/arch/arm/include/asm/system_misc.h b/arch/arm/include/asm/system_misc.h
index 8c4a89f..5b53a1c 100644
--- a/arch/arm/include/asm/system_misc.h
+++ b/arch/arm/include/asm/system_misc.h
@@ -22,7 +22,7 @@ extern void (*arm_pm_idle)(void);

extern unsigned int user_debug;

-static inline int handle_guest_sea(phys_addr_t addr, unsigned int esr)
+static inline int handle_guest_sea(unsigned int esr)
{
return -1;
}
diff --git a/arch/arm64/include/asm/system_misc.h b/arch/arm64/include/asm/system_misc.h
index 07aa8e3..3f0d0a8 100644
--- a/arch/arm64/include/asm/system_misc.h
+++ b/arch/arm64/include/asm/system_misc.h
@@ -56,7 +56,7 @@ 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);
+int handle_guest_sea(unsigned int esr);

#endif /* __ASSEMBLY__ */

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 2509e4f..13391f4 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -677,7 +677,7 @@ static const struct fault_info fault_info[] = {
* and non-zero if there was an error processing the error or there was
* no error to process.
*/
-int handle_guest_sea(phys_addr_t addr, unsigned int esr)
+int handle_guest_sea(unsigned int esr)
{
int ret = -ENOENT;

diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index d661d45..c15a08d 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -813,7 +813,6 @@ static struct notifier_block ghes_notifier_hed = {
.notifier_call = ghes_notify_hed,
};

-#ifdef CONFIG_ACPI_APEI_SEA
static LIST_HEAD(ghes_sea);

/*
@@ -848,19 +847,6 @@ static void ghes_sea_remove(struct ghes *ghes)
mutex_unlock(&ghes_list_mutex);
synchronize_rcu();
}
-#else /* CONFIG_ACPI_APEI_SEA */
-static inline void ghes_sea_add(struct ghes *ghes)
-{
- pr_err(GHES_PFX "ID: %d, trying to add SEA notification which is not supported\n",
- ghes->generic->header.source_id);
-}
-
-static inline void ghes_sea_remove(struct ghes *ghes)
-{
- pr_err(GHES_PFX "ID: %d, trying to remove SEA notification which is not supported\n",
- ghes->generic->header.source_id);
-}
-#endif /* CONFIG_ACPI_APEI_SEA */

#ifdef CONFIG_HAVE_ACPI_APEI_NMI
/*
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 2ea21da..07636c2 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -1504,7 +1504,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
* is no need to pass the error into the guest.
*/
if (is_abort_sea(fault_status)) {
- if (!handle_guest_sea(fault_ipa, kvm_vcpu_get_hsr(vcpu)))
+ if (!handle_guest_sea(kvm_vcpu_get_hsr(vcpu)))
return 1;
}

--
2.10.1