Re: [PATCH v4 4/5] powerpc/pseries/eeh: Implement RTAS-based EEH error injection
From: Narayana Murty N
Date: Mon Oct 19 2026 - 05:57:11 EST
Hi Sourabh,
On 23/09/26 3:52 PM, Sourabh Jain wrote:
Yes, this removes the last caller of eeh_pe_inject_mmio_error().
On 31/08/26 12:24, Narayana Murty N wrote:
Replace the legacy MMIO stub in pseries_eeh_err_inject() with a full
PAPR-compliant RTAS error injection path using the existing RTAS
work-area allocator.
The mutex is not a buffer lock; it serializes the firmware session
open/inject/close sequence as required by PAPR. No global buffer
is allocated or used.
VFIO EEH error injection exposes a generic userspace ABI. pSeries maps
the generic EEH error types to RTAS ibm,errinjct encodings via
pseries_eeh_type_to_rtas(). EEH_ERR_TYPE_32 and EEH_ERR_TYPE_64 are
unchanged; their values are defined in arch/powerpc/include/uapi/asm/ eeh.h
and are not renumbered.
Tested with corresponding QEMU patches:
https://lore.kernel.org/all/20251029150618.186803-1- nnmlinux@xxxxxxxxxxxxx/
Signed-off-by: Narayana Murty N <nnmlinux@xxxxxxxxxxxxx>
---
arch/powerpc/platforms/pseries/eeh_pseries.c | 123 ++++++++++++++-----
1 file changed, 95 insertions(+), 28 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/ powerpc/platforms/pseries/eeh_pseries.c
index fafe0004e738..fcb8c560d813 100644
--- a/arch/powerpc/platforms/pseries/eeh_pseries.c
+++ b/arch/powerpc/platforms/pseries/eeh_pseries.c
@@ -25,6 +25,7 @@
#include <linux/rbtree.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
+#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/crash_dump.h>
@@ -34,6 +35,7 @@
#include <asm/machdep.h>
#include <asm/ppc-pci.h>
#include <asm/rtas.h>
+#include <asm/rtas-work-area.h>
/* RTAS tokens */
static int ibm_set_eeh_option;
@@ -958,8 +960,6 @@ static int prepare_errinjct_buffer(void *buf, struct eeh_pe *pe,
return -EINVAL;
if (upper_32_bits(addr) || upper_32_bits(mask)) {
- pr_err("32-bit IOA injection cannot encode addr=%#lx mask=%#lx\n",
- addr, mask);
return -EINVAL;
}
@@ -992,50 +992,117 @@ static int prepare_errinjct_buffer(void *buf, struct eeh_pe *pe,
break;
default:
- pr_err("unsupported RTAS error injection type 0x%x\n", rtas_type);
+ pr_err("unsupported RTAS error injection type 0x%x\n",
+ rtas_type);
return -EINVAL;
}
- pr_debug("errinjct buffer ready: rtas_type=0x%x func=%d addr=0x%lx mask=0x%lx\n",
- rtas_type, func, addr, mask);
return 0;
}
+/* pseries-local mutex serializes the open/inject/close RTAS session */
+static DEFINE_MUTEX(pseries_errinjct_mutex);
+
/**
* pseries_eeh_err_inject - Inject specified error to the indicated PE
* @pe: the indicated PE
- * @type: error type
- * @func: specific error type
- * @addr: address
- * @mask: address mask
- * The routine is called to inject specified error, which is
- * determined by @type and @func, to the indicated PE
+ * @type: generic EEH error type (EEH_ERR_TYPE_32 or EEH_ERR_TYPE_64)
+ * @func: specific error function
+ * @addr: address argument (type-dependent, may be zero)
+ * @mask: address mask (type-dependent, may be zero)
+ *
+ * Implements PAPR-compliant error injection using:
+ * ibm,open-errinjct -> ibm,errinjct -> ibm,close-errinjct
+ *
+ * A short-lived RTAS work area is allocated per call; no global buffer
+ * is used. pseries_errinjct_mutex serializes the open/inject/close
+ * session sequence.
+ *
+ * Return: 0 on success, negative errno on failure.
*/
static int pseries_eeh_err_inject(struct eeh_pe *pe, int type, int func,
unsigned long addr, unsigned long mask)
{
- struct eeh_dev *pdev;
+ struct rtas_work_area *area;
+ phys_addr_t area_phys;
+ u32 buf_phys;
+ void *buf;
+ int open_token, errinjct_token, close_token;
+ int session_token;
+ int rtas_type;
+ int close_rc;
+ int rc;
+
+ rc = validate_errinjct_args(pe, type, func, addr, mask);
+ if (rc)
+ return rc;
- /* Check on PCI error type */
- if (type != EEH_ERR_TYPE_32 && type != EEH_ERR_TYPE_64)
+ rtas_type = pseries_eeh_type_to_rtas(type);
+ if (rtas_type < 0)
return -EINVAL;
- switch (func) {
- case EEH_ERR_FUNC_LD_MEM_ADDR:
- case EEH_ERR_FUNC_LD_MEM_DATA:
- case EEH_ERR_FUNC_ST_MEM_ADDR:
- case EEH_ERR_FUNC_ST_MEM_DATA:
- /* injects a MMIO error for all pdev's belonging to PE */
- pci_lock_rescan_remove();
- list_for_each_entry(pdev, &pe->edevs, entry)
- eeh_pe_inject_mmio_error(pdev->pdev);
Only caller of eeh_pe_inject_mmio_erro() is getting removed here. Should we remove the eeh_pe_inject_mmio_error() from the source?
I have removed eeh_pe_inject_mmio_error() and its declaration in v5.
Thanks,
Narayana
- pci_unlock_rescan_remove();
- break;
- default:
- return -ERANGE;
+ open_token = rtas_function_token(RTAS_FN_IBM_OPEN_ERRINJCT);
+ errinjct_token = rtas_function_token(RTAS_FN_IBM_ERRINJCT);
+ close_token = rtas_function_token(RTAS_FN_IBM_CLOSE_ERRINJCT);
+
+ if (open_token == RTAS_UNKNOWN_SERVICE ||
+ errinjct_token == RTAS_UNKNOWN_SERVICE ||
+ close_token == RTAS_UNKNOWN_SERVICE)
+ return -ENODEV;
+
+ area = rtas_work_area_alloc(RTAS_ERRINJCT_BUF_SIZE);
+ buf = rtas_work_area_raw_buf(area);
+ area_phys = rtas_work_area_phys(area);
+
+ if (WARN_ON_ONCE(upper_32_bits(area_phys))) {
+ rc = -ERANGE;
+ goto out_free_area;
}
- return 0;
+ buf_phys = lower_32_bits(area_phys);
+
+ rc = prepare_errinjct_buffer(buf, pe, rtas_type, func, addr, mask);
+ if (rc)
+ goto out_free_area;
+
+ mutex_lock(&pseries_errinjct_mutex);
+
+ do {
+ rc = rtas_call(open_token, 0, 2, &session_token);
+ } while (rtas_busy_delay(rc));
+
+ if (rc) {
+ pr_err("ibm,open-errinjct failed: status=%d\n", rc);
+ rc = rtas_error_rc(rc);
+ goto out_unlock;
+ }
+
+ do {
+ rc = rtas_call(errinjct_token, 3, 1, NULL,
+ rtas_type, session_token, buf_phys);
+ } while (rtas_busy_delay(rc));
+
+ if (rc) {
+ pr_err("ibm,errinjct failed: status=%d\n", rc);
+ rc = rtas_error_rc(rc);
+ }
+
+ do {
+ close_rc = rtas_call(close_token, 1, 1, NULL, session_token);
+ } while (rtas_busy_delay(close_rc));
+
+ if (close_rc) {
+ pr_warn("ibm,close-errinjct failed: status=%d\n", close_rc);
+ if (!rc)
+ rc = rtas_error_rc(close_rc);
+ }
+
+out_unlock:
+ mutex_unlock(&pseries_errinjct_mutex);
+
+out_free_area:
+ rtas_work_area_free(area);
+ return rc;
}
static struct eeh_ops pseries_eeh_ops = {