| Message ID | 20200408185834.434784-1-arnd@arndb.de (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 9d5100572474b2be7b313e9776117a8491f1fc72 |
| Headers | show |
| Series | soc: fsl: dpio: avoid stack usage warning | expand |
On Wed, Apr 08, 2020 at 08:58:16PM +0200, Arnd Bergmann wrote: > 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@arndb.de> > --- > 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); I think you need to rearrange this to be more compliant with the coding style. > + 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 > >
On Wed, Apr 8, 2020 at 10:24 PM Russell King - ARM Linux admin <linux@armlinux.org.uk> wrote: > On Wed, Apr 08, 2020 at 08:58:16PM +0200, Arnd Bergmann wrote: > > - int i; > > - struct qbman_eq_desc ed[32]; > > + struct qbman_eq_desc *ed = kcalloc(sizeof(struct qbman_eq_desc), 32, GFP_KERNEL); > > I think you need to rearrange this to be more compliant with the coding > style. Ok, I've updated this now to move the allocation into a new line and applied this and the other fsl patch into the arm/fixes branch for v5.7. Arnd
Hello: This patch was applied to soc/soc.git (refs/heads/for-next). On Wed, 8 Apr 2020 20:58:16 +0200 you wrote: > 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. > > [...] Here is a summary with links: - soc: fsl: dpio: avoid stack usage warning https://git.kernel.org/soc/soc/c/9d5100572474b2be7b313e9776117a8491f1fc72 You are awesome, thank you!
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);
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@arndb.de> --- drivers/soc/fsl/dpio/dpio-service.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)