2024-05-16 07:38:02

by Peng Fan (OSS)

Subject: [PATCH] vhost: use pr_err for vq_err

From: Peng Fan <[email protected]>

Use pr_err to print out error message without enabling DEBUG. This could
make people catch error easier.

Signed-off-by: Peng Fan <[email protected]>
---
drivers/vhost/vhost.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index bb75a292d50c..0bff436d1ce9 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -248,7 +248,7 @@ void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
struct vhost_iotlb_map *map);

#define vq_err(vq, fmt, ...) do { \
- pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
+ pr_err(pr_fmt(fmt), ##__VA_ARGS__); \
if ((vq)->error_ctx) \
eventfd_signal((vq)->error_ctx);\
} while (0)
--
2.37.1

2024-05-16 12:33:45

by Michael S. Tsirkin

Subject: Re: [PATCH] vhost: use pr_err for vq_err

On Thu, May 16, 2024 at 03:46:29PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <[email protected]>
>
> Use pr_err to print out error message without enabling DEBUG. This could
> make people catch error easier.
>
> Signed-off-by: Peng Fan <[email protected]>

This isn't appropriate: pr_err must not be triggerable
by userspace. If you are debugging userspace, use a debugging
kernel, it's that simple.


> ---
> drivers/vhost/vhost.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> index bb75a292d50c..0bff436d1ce9 100644
> --- a/drivers/vhost/vhost.h
> +++ b/drivers/vhost/vhost.h
> @@ -248,7 +248,7 @@ void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
> struct vhost_iotlb_map *map);
>
> #define vq_err(vq, fmt, ...) do { \
> - pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
> + pr_err(pr_fmt(fmt), ##__VA_ARGS__); \
> if ((vq)->error_ctx) \
> eventfd_signal((vq)->error_ctx);\
> } while (0)
> --
> 2.37.1

2024-05-16 12:36:35

by Peng Fan

Subject: RE: [PATCH] vhost: use pr_err for vq_err

> Subject: Re: [PATCH] vhost: use pr_err for vq_err
>
> On Thu, May 16, 2024 at 03:46:29PM +0800, Peng Fan (OSS) wrote:
> > From: Peng Fan <[email protected]>
> >
> > Use pr_err to print out error message without enabling DEBUG. This
> > could make people catch error easier.
> >
> > Signed-off-by: Peng Fan <[email protected]>
>
> This isn't appropriate: pr_err must not be triggerable by userspace. If you are
> debugging userspace, use a debugging kernel, it's that simple.

I see, then drop this patch.

Thanks,
Peng.
>
>
> > ---
> > drivers/vhost/vhost.h | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index
> > bb75a292d50c..0bff436d1ce9 100644
> > --- a/drivers/vhost/vhost.h
> > +++ b/drivers/vhost/vhost.h
> > @@ -248,7 +248,7 @@ void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
> > struct vhost_iotlb_map *map);
> >
> > #define vq_err(vq, fmt, ...) do { \
> > - pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
> > + pr_err(pr_fmt(fmt), ##__VA_ARGS__); \
> > if ((vq)->error_ctx) \
> > eventfd_signal((vq)->error_ctx);\
> > } while (0)
> > --
> > 2.37.1