Commit 3f77c3dfffc7 for kernel
commit 3f77c3dfffc7063428b100c4945ca2a7a8680380
Author: Shannon Nelson <shannon.nelson@amd.com>
Date: Mon Apr 21 10:46:06 2025 -0700
pds_core: make wait_context part of q_info
Make the wait_context a full part of the q_info struct rather
than a stack variable that goes away after pdsc_adminq_post()
is done so that the context is still available after the wait
loop has given up.
There was a case where a slow development firmware caused
the adminq request to time out, but then later the FW finally
finished the request and sent the interrupt. The handler tried
to complete_all() the completion context that had been created
on the stack in pdsc_adminq_post() but no longer existed.
This caused bad pointer usage, kernel crashes, and much wailing
and gnashing of teeth.
Fixes: 01ba61b55b20 ("pds_core: Add adminq processing and commands")
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20250421174606.3892-5-shannon.nelson@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
diff --git a/drivers/net/ethernet/amd/pds_core/adminq.c b/drivers/net/ethernet/amd/pds_core/adminq.c
index c83a0a80d533..506f682d15c1 100644
--- a/drivers/net/ethernet/amd/pds_core/adminq.c
+++ b/drivers/net/ethernet/amd/pds_core/adminq.c
@@ -5,11 +5,6 @@
#include "core.h"
-struct pdsc_wait_context {
- struct pdsc_qcq *qcq;
- struct completion wait_completion;
-};
-
static int pdsc_process_notifyq(struct pdsc_qcq *qcq)
{
union pds_core_notifyq_comp *comp;
@@ -109,10 +104,10 @@ void pdsc_process_adminq(struct pdsc_qcq *qcq)
q_info = &q->info[q->tail_idx];
q->tail_idx = (q->tail_idx + 1) & (q->num_descs - 1);
- /* Copy out the completion data */
- memcpy(q_info->dest, comp, sizeof(*comp));
-
- complete_all(&q_info->wc->wait_completion);
+ if (!completion_done(&q_info->completion)) {
+ memcpy(q_info->dest, comp, sizeof(*comp));
+ complete(&q_info->completion);
+ }
if (cq->tail_idx == cq->num_descs - 1)
cq->done_color = !cq->done_color;
@@ -162,8 +157,7 @@ irqreturn_t pdsc_adminq_isr(int irq, void *data)
static int __pdsc_adminq_post(struct pdsc *pdsc,
struct pdsc_qcq *qcq,
union pds_core_adminq_cmd *cmd,
- union pds_core_adminq_comp *comp,
- struct pdsc_wait_context *wc)
+ union pds_core_adminq_comp *comp)
{
struct pdsc_queue *q = &qcq->q;
struct pdsc_q_info *q_info;
@@ -205,9 +199,9 @@ static int __pdsc_adminq_post(struct pdsc *pdsc,
/* Post the request */
index = q->head_idx;
q_info = &q->info[index];
- q_info->wc = wc;
q_info->dest = comp;
memcpy(q_info->desc, cmd, sizeof(*cmd));
+ reinit_completion(&q_info->completion);
dev_dbg(pdsc->dev, "head_idx %d tail_idx %d\n",
q->head_idx, q->tail_idx);
@@ -231,16 +225,13 @@ int pdsc_adminq_post(struct pdsc *pdsc,
union pds_core_adminq_comp *comp,
bool fast_poll)
{
- struct pdsc_wait_context wc = {
- .wait_completion =
- COMPLETION_INITIALIZER_ONSTACK(wc.wait_completion),
- };
unsigned long poll_interval = 1;
unsigned long poll_jiffies;
unsigned long time_limit;
unsigned long time_start;
unsigned long time_done;
unsigned long remaining;
+ struct completion *wc;
int err = 0;
int index;
@@ -250,20 +241,19 @@ int pdsc_adminq_post(struct pdsc *pdsc,
return -ENXIO;
}
- wc.qcq = &pdsc->adminqcq;
- index = __pdsc_adminq_post(pdsc, &pdsc->adminqcq, cmd, comp, &wc);
+ index = __pdsc_adminq_post(pdsc, &pdsc->adminqcq, cmd, comp);
if (index < 0) {
err = index;
goto err_out;
}
+ wc = &pdsc->adminqcq.q.info[index].completion;
time_start = jiffies;
time_limit = time_start + HZ * pdsc->devcmd_timeout;
do {
/* Timeslice the actual wait to catch IO errors etc early */
poll_jiffies = msecs_to_jiffies(poll_interval);
- remaining = wait_for_completion_timeout(&wc.wait_completion,
- poll_jiffies);
+ remaining = wait_for_completion_timeout(wc, poll_jiffies);
if (remaining)
break;
@@ -292,9 +282,11 @@ int pdsc_adminq_post(struct pdsc *pdsc,
dev_dbg(pdsc->dev, "%s: elapsed %d msecs\n",
__func__, jiffies_to_msecs(time_done - time_start));
- /* Check the results */
- if (time_after_eq(time_done, time_limit))
+ /* Check the results and clear an un-completed timeout */
+ if (time_after_eq(time_done, time_limit) && !completion_done(wc)) {
err = -ETIMEDOUT;
+ complete(wc);
+ }
dev_dbg(pdsc->dev, "read admin queue completion idx %d:\n", index);
dynamic_hex_dump("comp ", DUMP_PREFIX_OFFSET, 16, 1,
diff --git a/drivers/net/ethernet/amd/pds_core/core.c b/drivers/net/ethernet/amd/pds_core/core.c
index 55163457f12b..9512aa4083f0 100644
--- a/drivers/net/ethernet/amd/pds_core/core.c
+++ b/drivers/net/ethernet/amd/pds_core/core.c
@@ -167,8 +167,10 @@ static void pdsc_q_map(struct pdsc_queue *q, void *base, dma_addr_t base_pa)
q->base = base;
q->base_pa = base_pa;
- for (i = 0, cur = q->info; i < q->num_descs; i++, cur++)
+ for (i = 0, cur = q->info; i < q->num_descs; i++, cur++) {
cur->desc = base + (i * q->desc_size);
+ init_completion(&cur->completion);
+ }
}
static void pdsc_cq_map(struct pdsc_cq *cq, void *base, dma_addr_t base_pa)
diff --git a/drivers/net/ethernet/amd/pds_core/core.h b/drivers/net/ethernet/amd/pds_core/core.h
index 199473112c29..0b53a1fab46d 100644
--- a/drivers/net/ethernet/amd/pds_core/core.h
+++ b/drivers/net/ethernet/amd/pds_core/core.h
@@ -96,7 +96,7 @@ struct pdsc_q_info {
unsigned int bytes;
unsigned int nbufs;
struct pdsc_buf_info bufs[PDS_CORE_MAX_FRAGS];
- struct pdsc_wait_context *wc;
+ struct completion completion;
void *dest;
};