Refactors the GHES driver by extracting common functionality into
reusable helper functions:
1. ghes_has_active_errors() - Checks if any error sources in a given list
have active errors
2. ghes_map_error_status() - Maps error status address to virtual address
3. ghes_unmap_error_status() - Unmaps error status virtual address
These helpers eliminate code duplication in the NMI path and prepare for
similar usage in the SEA path in a subsequent patch.
No functional change intended.
Tested-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
---
drivers/acpi/apei/ghes.c | 93 +++++++++++++++++++++++++++++++---------
1 file changed, 72 insertions(+), 21 deletions(-)
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 0e97d50b0240..7600063fe263 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -1406,6 +1406,75 @@ static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
return ret;
}
+/**
+ * ghes_has_active_errors - Check if there are active errors in error sources
+ * @ghes_list: List of GHES entries to check for active errors
+ *
+ * This function iterates through all GHES entries in the given list and
+ * checks if any of them has active error status by reading the error
+ * status register.
+ *
+ * Return: true if at least one source has active error, false otherwise.
+ */
+static bool __maybe_unused ghes_has_active_errors(struct list_head *ghes_list)
+{
+ bool active_error = false;
+ struct ghes *ghes;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ghes, ghes_list, list) {
+ if (ghes->error_status_vaddr &&
+ readl(ghes->error_status_vaddr)) {
+ active_error = true;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ return active_error;
+}
+
+/**
+ * ghes_map_error_status - Map error status address to virtual address
+ * @ghes: pointer to GHES structure
+ *
+ * Reads the error status address from ACPI HEST table and maps it to a virtual
+ * address that can be accessed by the kernel.
+ *
+ * Return: 0 on success, error code on failure.
+ */
+static int __maybe_unused ghes_map_error_status(struct ghes *ghes)
+{
+ struct acpi_hest_generic *g = ghes->generic;
+ u64 paddr;
+ int rc;
+
+ rc = apei_read(&paddr, &g->error_status_address);
+ if (rc)
+ return rc;
+
+ ghes->error_status_vaddr =
+ acpi_os_ioremap(paddr, sizeof(ghes->estatus->block_status));
+ if (!ghes->error_status_vaddr)
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * ghes_unmap_error_status - Unmap error status virtual address
+ * @ghes: pointer to GHES structure
+ *
+ * Unmaps the error status address if it was previously mapped.
+ */
+static void __maybe_unused ghes_unmap_error_status(struct ghes *ghes)
+{
+ if (ghes->error_status_vaddr) {
+ iounmap(ghes->error_status_vaddr);
+ ghes->error_status_vaddr = NULL;
+ }
+}
+
#ifdef CONFIG_ACPI_APEI_SEA
static LIST_HEAD(ghes_sea);
@@ -1456,20 +1525,9 @@ static LIST_HEAD(ghes_nmi);
static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
{
static DEFINE_RAW_SPINLOCK(ghes_notify_lock_nmi);
- bool active_error = false;
int ret = NMI_DONE;
- struct ghes *ghes;
-
- rcu_read_lock();
- list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
- if (ghes->error_status_vaddr && readl(ghes->error_status_vaddr)) {
- active_error = true;
- break;
- }
- }
- rcu_read_unlock();
- if (!active_error)
+ if (!ghes_has_active_errors(&ghes_nmi))
return ret;
if (!atomic_add_unless(&ghes_in_nmi, 1, 1))
@@ -1486,18 +1544,12 @@ static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
static int ghes_nmi_add(struct ghes *ghes)
{
- struct acpi_hest_generic *g = ghes->generic;
- u64 paddr;
int rc;
- rc = apei_read(&paddr, &g->error_status_address);
+ rc = ghes_map_error_status(ghes);
if (rc)
return rc;
- ghes->error_status_vaddr = acpi_os_ioremap(paddr, sizeof(ghes->estatus->block_status));
- if (!ghes->error_status_vaddr)
- return -EINVAL;
-
mutex_lock(&ghes_list_mutex);
if (list_empty(&ghes_nmi))
register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes");
@@ -1515,8 +1567,7 @@ static void ghes_nmi_remove(struct ghes *ghes)
unregister_nmi_handler(NMI_LOCAL, "ghes");
mutex_unlock(&ghes_list_mutex);
- if (ghes->error_status_vaddr)
- iounmap(ghes->error_status_vaddr);
+ ghes_unmap_error_status(ghes);
/*
* To synchronize with NMI handler, ghes can only be
--
2.39.3On Sun, Jan 4, 2026 at 8:05 PM Shuai Xue <xueshuai@linux.alibaba.com> wrote:
>
> Refactors the GHES driver by extracting common functionality into
> reusable helper functions:
>
> 1. ghes_has_active_errors() - Checks if any error sources in a given list
> have active errors
> 2. ghes_map_error_status() - Maps error status address to virtual address
> 3. ghes_unmap_error_status() - Unmaps error status virtual address
>
> These helpers eliminate code duplication in the NMI path and prepare for
> similar usage in the SEA path in a subsequent patch.
>
> No functional change intended.
>
> Tested-by: Tony Luck <tony.luck@intel.com>
> Reviewed-by: Tony Luck <tony.luck@intel.com>
> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
> ---
> drivers/acpi/apei/ghes.c | 93 +++++++++++++++++++++++++++++++---------
> 1 file changed, 72 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index 0e97d50b0240..7600063fe263 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -1406,6 +1406,75 @@ static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
> return ret;
> }
>
> +/**
> + * ghes_has_active_errors - Check if there are active errors in error sources
> + * @ghes_list: List of GHES entries to check for active errors
> + *
> + * This function iterates through all GHES entries in the given list and
> + * checks if any of them has active error status by reading the error
> + * status register.
> + *
> + * Return: true if at least one source has active error, false otherwise.
> + */
> +static bool __maybe_unused ghes_has_active_errors(struct list_head *ghes_list)
> +{
> + bool active_error = false;
> + struct ghes *ghes;
> +
> + rcu_read_lock();
Nit: Use `guard(rcu)()` instead of explicit
`rcu_read_lock()`/`rcu_read_unlock()`.
Thanks,
Donglin
> + list_for_each_entry_rcu(ghes, ghes_list, list) {
> + if (ghes->error_status_vaddr &&
> + readl(ghes->error_status_vaddr)) {
> + active_error = true;
> + break;
> + }
> + }
> + rcu_read_unlock();
> +
> + return active_error;
> +}
> +
> +/**
> + * ghes_map_error_status - Map error status address to virtual address
> + * @ghes: pointer to GHES structure
> + *
> + * Reads the error status address from ACPI HEST table and maps it to a virtual
> + * address that can be accessed by the kernel.
> + *
> + * Return: 0 on success, error code on failure.
> + */
> +static int __maybe_unused ghes_map_error_status(struct ghes *ghes)
> +{
> + struct acpi_hest_generic *g = ghes->generic;
> + u64 paddr;
> + int rc;
> +
> + rc = apei_read(&paddr, &g->error_status_address);
> + if (rc)
> + return rc;
> +
> + ghes->error_status_vaddr =
> + acpi_os_ioremap(paddr, sizeof(ghes->estatus->block_status));
> + if (!ghes->error_status_vaddr)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +/**
> + * ghes_unmap_error_status - Unmap error status virtual address
> + * @ghes: pointer to GHES structure
> + *
> + * Unmaps the error status address if it was previously mapped.
> + */
> +static void __maybe_unused ghes_unmap_error_status(struct ghes *ghes)
> +{
> + if (ghes->error_status_vaddr) {
> + iounmap(ghes->error_status_vaddr);
> + ghes->error_status_vaddr = NULL;
> + }
> +}
> +
> #ifdef CONFIG_ACPI_APEI_SEA
> static LIST_HEAD(ghes_sea);
>
> @@ -1456,20 +1525,9 @@ static LIST_HEAD(ghes_nmi);
> static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
> {
> static DEFINE_RAW_SPINLOCK(ghes_notify_lock_nmi);
> - bool active_error = false;
> int ret = NMI_DONE;
> - struct ghes *ghes;
> -
> - rcu_read_lock();
> - list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
> - if (ghes->error_status_vaddr && readl(ghes->error_status_vaddr)) {
> - active_error = true;
> - break;
> - }
> - }
> - rcu_read_unlock();
>
> - if (!active_error)
> + if (!ghes_has_active_errors(&ghes_nmi))
> return ret;
>
> if (!atomic_add_unless(&ghes_in_nmi, 1, 1))
> @@ -1486,18 +1544,12 @@ static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs)
>
> static int ghes_nmi_add(struct ghes *ghes)
> {
> - struct acpi_hest_generic *g = ghes->generic;
> - u64 paddr;
> int rc;
>
> - rc = apei_read(&paddr, &g->error_status_address);
> + rc = ghes_map_error_status(ghes);
> if (rc)
> return rc;
>
> - ghes->error_status_vaddr = acpi_os_ioremap(paddr, sizeof(ghes->estatus->block_status));
> - if (!ghes->error_status_vaddr)
> - return -EINVAL;
> -
> mutex_lock(&ghes_list_mutex);
> if (list_empty(&ghes_nmi))
> register_nmi_handler(NMI_LOCAL, ghes_notify_nmi, 0, "ghes");
> @@ -1515,8 +1567,7 @@ static void ghes_nmi_remove(struct ghes *ghes)
> unregister_nmi_handler(NMI_LOCAL, "ghes");
> mutex_unlock(&ghes_list_mutex);
>
> - if (ghes->error_status_vaddr)
> - iounmap(ghes->error_status_vaddr);
> + ghes_unmap_error_status(ghes);
>
> /*
> * To synchronize with NMI handler, ghes can only be
> --
> 2.39.3
>
>
On 1/5/26 1:12 PM, Donglin Peng wrote:
> On Sun, Jan 4, 2026 at 8:05 PM Shuai Xue <xueshuai@linux.alibaba.com> wrote:
>>
>> Refactors the GHES driver by extracting common functionality into
>> reusable helper functions:
>>
>> 1. ghes_has_active_errors() - Checks if any error sources in a given list
>> have active errors
>> 2. ghes_map_error_status() - Maps error status address to virtual address
>> 3. ghes_unmap_error_status() - Unmaps error status virtual address
>>
>> These helpers eliminate code duplication in the NMI path and prepare for
>> similar usage in the SEA path in a subsequent patch.
>>
>> No functional change intended.
>>
>> Tested-by: Tony Luck <tony.luck@intel.com>
>> Reviewed-by: Tony Luck <tony.luck@intel.com>
>> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
>> ---
>> drivers/acpi/apei/ghes.c | 93 +++++++++++++++++++++++++++++++---------
>> 1 file changed, 72 insertions(+), 21 deletions(-)
>>
>> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
>> index 0e97d50b0240..7600063fe263 100644
>> --- a/drivers/acpi/apei/ghes.c
>> +++ b/drivers/acpi/apei/ghes.c
>> @@ -1406,6 +1406,75 @@ static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
>> return ret;
>> }
>>
>> +/**
>> + * ghes_has_active_errors - Check if there are active errors in error sources
>> + * @ghes_list: List of GHES entries to check for active errors
>> + *
>> + * This function iterates through all GHES entries in the given list and
>> + * checks if any of them has active error status by reading the error
>> + * status register.
>> + *
>> + * Return: true if at least one source has active error, false otherwise.
>> + */
>> +static bool __maybe_unused ghes_has_active_errors(struct list_head *ghes_list)
>> +{
>> + bool active_error = false;
>> + struct ghes *ghes;
>> +
>> + rcu_read_lock();
>
> Nit: Use `guard(rcu)()` instead of explicit
> `rcu_read_lock()`/`rcu_read_unlock()`.
>
> Thanks,
> Donglin
>
Hi, Donglin,
Good point. Will fix in next version.
Thanks.
Shuai
On Mon, Jan 5, 2026 at 6:42 AM Shuai Xue <xueshuai@linux.alibaba.com> wrote:
>
>
>
> On 1/5/26 1:12 PM, Donglin Peng wrote:
> > On Sun, Jan 4, 2026 at 8:05 PM Shuai Xue <xueshuai@linux.alibaba.com> wrote:
> >>
> >> Refactors the GHES driver by extracting common functionality into
> >> reusable helper functions:
> >>
> >> 1. ghes_has_active_errors() - Checks if any error sources in a given list
> >> have active errors
> >> 2. ghes_map_error_status() - Maps error status address to virtual address
> >> 3. ghes_unmap_error_status() - Unmaps error status virtual address
> >>
> >> These helpers eliminate code duplication in the NMI path and prepare for
> >> similar usage in the SEA path in a subsequent patch.
> >>
> >> No functional change intended.
> >>
> >> Tested-by: Tony Luck <tony.luck@intel.com>
> >> Reviewed-by: Tony Luck <tony.luck@intel.com>
> >> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
> >> ---
> >> drivers/acpi/apei/ghes.c | 93 +++++++++++++++++++++++++++++++---------
> >> 1 file changed, 72 insertions(+), 21 deletions(-)
> >>
> >> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> >> index 0e97d50b0240..7600063fe263 100644
> >> --- a/drivers/acpi/apei/ghes.c
> >> +++ b/drivers/acpi/apei/ghes.c
> >> @@ -1406,6 +1406,75 @@ static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
> >> return ret;
> >> }
> >>
> >> +/**
> >> + * ghes_has_active_errors - Check if there are active errors in error sources
> >> + * @ghes_list: List of GHES entries to check for active errors
> >> + *
> >> + * This function iterates through all GHES entries in the given list and
> >> + * checks if any of them has active error status by reading the error
> >> + * status register.
> >> + *
> >> + * Return: true if at least one source has active error, false otherwise.
> >> + */
> >> +static bool __maybe_unused ghes_has_active_errors(struct list_head *ghes_list)
> >> +{
> >> + bool active_error = false;
> >> + struct ghes *ghes;
> >> +
> >> + rcu_read_lock();
> >
> > Nit: Use `guard(rcu)()` instead of explicit
> > `rcu_read_lock()`/`rcu_read_unlock()`.
> >
> > Thanks,
> > Donglin
> >
>
> Hi, Donglin,
>
> Good point. Will fix in next version.
If you do so, you may also get rid of the active_error local variable.
On 1/10/26 5:22 AM, Rafael J. Wysocki wrote:
> On Mon, Jan 5, 2026 at 6:42 AM Shuai Xue <xueshuai@linux.alibaba.com> wrote:
>>
>>
>>
>> On 1/5/26 1:12 PM, Donglin Peng wrote:
>>> On Sun, Jan 4, 2026 at 8:05 PM Shuai Xue <xueshuai@linux.alibaba.com> wrote:
>>>>
>>>> Refactors the GHES driver by extracting common functionality into
>>>> reusable helper functions:
>>>>
>>>> 1. ghes_has_active_errors() - Checks if any error sources in a given list
>>>> have active errors
>>>> 2. ghes_map_error_status() - Maps error status address to virtual address
>>>> 3. ghes_unmap_error_status() - Unmaps error status virtual address
>>>>
>>>> These helpers eliminate code duplication in the NMI path and prepare for
>>>> similar usage in the SEA path in a subsequent patch.
>>>>
>>>> No functional change intended.
>>>>
>>>> Tested-by: Tony Luck <tony.luck@intel.com>
>>>> Reviewed-by: Tony Luck <tony.luck@intel.com>
>>>> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
>>>> ---
>>>> drivers/acpi/apei/ghes.c | 93 +++++++++++++++++++++++++++++++---------
>>>> 1 file changed, 72 insertions(+), 21 deletions(-)
>>>>
>>>> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
>>>> index 0e97d50b0240..7600063fe263 100644
>>>> --- a/drivers/acpi/apei/ghes.c
>>>> +++ b/drivers/acpi/apei/ghes.c
>>>> @@ -1406,6 +1406,75 @@ static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list,
>>>> return ret;
>>>> }
>>>>
>>>> +/**
>>>> + * ghes_has_active_errors - Check if there are active errors in error sources
>>>> + * @ghes_list: List of GHES entries to check for active errors
>>>> + *
>>>> + * This function iterates through all GHES entries in the given list and
>>>> + * checks if any of them has active error status by reading the error
>>>> + * status register.
>>>> + *
>>>> + * Return: true if at least one source has active error, false otherwise.
>>>> + */
>>>> +static bool __maybe_unused ghes_has_active_errors(struct list_head *ghes_list)
>>>> +{
>>>> + bool active_error = false;
>>>> + struct ghes *ghes;
>>>> +
>>>> + rcu_read_lock();
>>>
>>> Nit: Use `guard(rcu)()` instead of explicit
>>> `rcu_read_lock()`/`rcu_read_unlock()`.
>>>
>>> Thanks,
>>> Donglin
>>>
>>
>> Hi, Donglin,
>>
>> Good point. Will fix in next version.
>
> If you do so, you may also get rid of the active_error local variable.
Got it. Thanks for reminding.
Shuai
© 2016 - 2026 Red Hat, Inc.