6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Muhammad Usama Anjum usama.anjum@collabora.com
[ Upstream commit cd2e7bae92bd7e65063ab8d04721d2b711ba4cbe ]
Firmware requests 2 segments at first. The first segment is of 6799360 whose allocation fails due to dma remapping not available. The success is returned to firmware. Then firmware asks for 22 smaller segments instead of 2 big ones. Those get allocated successfully. At suspend/ hibernation time, these segments aren't freed as they will be reused by firmware after resuming.
After resuming, the firmware asks for the 2 segments again with the first segment of 6799360 size. Since chunk->vaddr is not NULL, the type and size are compared with the previous type and size to know if it can be reused or not. Unfortunately, it is detected that it cannot be reused and this first smaller segment is freed. Then we continue to allocate 6799360 size memory which fails and ath11k_qmi_free_target_mem_chunk() is called which frees the second smaller segment as well. Later success is returned to firmware which asks for 22 smaller segments again. But as we had freed 2 segments already, we'll allocate the first 2 new smaller segments again and reuse the remaining 20. Hence 20 small segments are being reused instead of 22.
Add skip logic when vaddr is set, but size/type don't match. Use the same skip and success logic as used when dma_alloc_coherent() fails. By skipping, the possibility of resume failure due to kernel failing to allocate memory for QMI can be avoided.
kernel: ath11k_pci 0000:03:00.0: failed to allocate dma memory for qmi (524288 B type 1) ath11k_pci 0000:03:00.0: failed to allocate qmi target memory: -22
Tested-on: WCN6855 WLAN.HSP.1.1-03926.13-QCAHSPSWPL_V2_SILICONZ_CE-2.52297.6
Signed-off-by: Muhammad Usama Anjum usama.anjum@collabora.com Reviewed-by: Baochen Qiang quic_bqiang@quicinc.com Link: https://patch.msgid.link/20250428080242.466901-1-usama.anjum@collabora.com Signed-off-by: Jeff Johnson jeff.johnson@oss.qualcomm.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/ath/ath11k/qmi.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/net/wireless/ath/ath11k/qmi.c b/drivers/net/wireless/ath/ath11k/qmi.c index fa46e645009cf..91e31f30d2c80 100644 --- a/drivers/net/wireless/ath/ath11k/qmi.c +++ b/drivers/net/wireless/ath/ath11k/qmi.c @@ -1989,6 +1989,15 @@ static int ath11k_qmi_alloc_target_mem_chunk(struct ath11k_base *ab) chunk->prev_size == chunk->size) continue;
+ if (ab->qmi.mem_seg_count <= ATH11K_QMI_FW_MEM_REQ_SEGMENT_CNT) { + ath11k_dbg(ab, ATH11K_DBG_QMI, + "size/type mismatch (current %d %u) (prev %d %u), try later with small size\n", + chunk->size, chunk->type, + chunk->prev_size, chunk->prev_type); + ab->qmi.target_mem_delayed = true; + return 0; + } + /* cannot reuse the existing chunk */ dma_free_coherent(ab->dev, chunk->prev_size, chunk->vaddr, chunk->paddr);