[PATCH] soc: fsl: dpio: avoid stack usage warning

From: Arnd Bergmann
Date: Wed Apr 08 2020 - 14:58:51 EST


A 1024 byte variable on the stack will warn on any 32-bit architecture
during compile-testing, and is generally a bad idea anyway:

fsl/dpio/dpio-service.c: In function 'dpaa2_io_service_enqueue_multiple_desc_fq':
fsl/dpio/dpio-service.c:495:1: error: the frame size of 1032 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

There are currently no callers of this function, so I cannot tell whether
dynamic memory allocation is allowed once callers are added. Change
it to kcalloc for now, if anyone gets a warning about calling this in
atomic context after they start using it, they can fix it later.

Fixes: 9d98809711ae ("soc: fsl: dpio: Adding QMAN multiple enqueue interface")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/soc/fsl/dpio/dpio-service.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/soc/fsl/dpio/dpio-service.c b/drivers/soc/fsl/dpio/dpio-service.c
index cd4f6410e8c2..ff0ef8cbdbff 100644
--- a/drivers/soc/fsl/dpio/dpio-service.c
+++ b/drivers/soc/fsl/dpio/dpio-service.c
@@ -478,12 +478,17 @@ int dpaa2_io_service_enqueue_multiple_desc_fq(struct dpaa2_io *d,
const struct dpaa2_fd *fd,
int nb)
{
- int i;
- struct qbman_eq_desc ed[32];
+ struct qbman_eq_desc *ed = kcalloc(sizeof(struct qbman_eq_desc), 32, GFP_KERNEL);
+ int i, ret;
+
+ if (!ed)
+ return -ENOMEM;

d = service_select(d);
- if (!d)
- return -ENODEV;
+ if (!d) {
+ ret = -ENODEV;
+ goto out;
+ }

for (i = 0; i < nb; i++) {
qbman_eq_desc_clear(&ed[i]);
@@ -491,7 +496,10 @@ int dpaa2_io_service_enqueue_multiple_desc_fq(struct dpaa2_io *d,
qbman_eq_desc_set_fq(&ed[i], fqid[i]);
}

- return qbman_swp_enqueue_multiple_desc(d->swp, &ed[0], fd, nb);
+ ret = qbman_swp_enqueue_multiple_desc(d->swp, &ed[0], fd, nb);
+out:
+ kfree(ed);
+ return ret;
}
EXPORT_SYMBOL(dpaa2_io_service_enqueue_multiple_desc_fq);

--
2.26.0