Re: [PATCH v3] dmaengine: qcom: gpi: Fix resource leaks as part of channel clean up

From: Praveen Talari

Date: Fri Aug 21 2026 - 01:12:29 EST



On 19-08-2026 17:09, Aniket Randive wrote:
The gpi_ch_init() error handling paths do not fully clean up resources
when channel initialization fails.

The unwind paths iterate over the original channel pointer instead of
the channels stored in gpii->gchan[], preventing previously initialized
sibling channels from being properly reset and deallocated.

In addition, gpi_alloc_chan_resources() allocates ch_ring before calling
gpi_ch_init(), but does not release it when initialization fails,
resulting in a memory leak.

The event ring cleanup path also leaves the PM state unchanged after
freeing the ring. As a result, subsequent cleanup may incorrectly assume
that the ring is still allocated, leading to a redundant EV_CMD_DEALLOC
command and an attempt to deallocate an already released ring.

Fix the unwind paths to operate on the correct channels, release
ch_ring when channel initialization fails, and restore the event ring
PM state after freeing the ring.

Signed-off-by: Aniket Randive <aniket.randive@xxxxxxxxxxxxxxxx>
---
Changes in v3:
- Updated the commit message as per Mukesh suggestion.
- Link to v2: https://patch.msgid.link/20260810-gpi_bug_fix-v2-1-60555394cbf9@xxxxxxxxxxxxxxxx

Changes in v2:
- Updated the commit message as per Mukesh suggestion.
---
drivers/dma/qcom/gpi.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c
index a5055a6273af..c41bfac65ddf 100644
--- a/drivers/dma/qcom/gpi.c
+++ b/drivers/dma/qcom/gpi.c
@@ -1965,16 +1965,19 @@ static int gpi_ch_init(struct gchan *gchan)
error_start_chan:
for (i = i - 1; i >= 0; i--) {
gpi_stop_chan(&gpii->gchan[i]);
- gpi_send_cmd(gpii, gchan, GPI_CH_CMD_RESET);
+ gpi_send_cmd(gpii, &gpii->gchan[i], GPI_CH_CMD_RESET);
}
i = 2;
error_alloc_chan:
for (i = i - 1; i >= 0; i--)
- gpi_reset_chan(gchan, GPI_CH_CMD_DE_ALLOC);
+ gpi_reset_chan(&gpii->gchan[i], GPI_CH_CMD_DE_ALLOC);
error_alloc_ev_ring:
gpi_disable_interrupts(gpii);
error_config_int:
gpi_free_ring(&gpii->ev_ring, gpii);
+ write_lock_irq(&gpii->pm_lock);
+ gpii->pm_state = DISABLE_STATE;
+ write_unlock_irq(&gpii->pm_lock);
exit_gpi_init:
return ret;
}
@@ -2065,6 +2068,8 @@ static int gpi_alloc_chan_resources(struct dma_chan *chan)
goto xfer_alloc_err;
ret = gpi_ch_init(gchan);
+ if (ret)
+ gpi_free_ring(&gchan->ch_ring, gpii);

Reviewed-by: Praveen Talari <praveen.talari@xxxxxxxxxxxxxxxx>

Thanks,

Praveen Talari

mutex_unlock(&gpii->ctrl_lock);

---
base-commit: 415606a7be939835db9b0d6b711887586646346d
change-id: 20260803-gpi_bug_fix-b0b80ef315b5

Best regards,
--
Aniket Randive <aniket.randive@xxxxxxxxxxxxxxxx>