| Message ID | 20250302143259.1221569-9-lulu@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | vhost: Add support of kthread API | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Sun, Mar 2, 2025 at 10:34 PM Cindy Lu <lulu@redhat.com> wrote: > > Introduce a new config knob `CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL`, > to control the availability of the `VHOST_FORK_FROM_OWNER` ioctl. > When CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL is set to n, the ioctl > is disabled, and any attempt to use it will result in failure. > > Signed-off-by: Cindy Lu <lulu@redhat.com> > --- > drivers/vhost/Kconfig | 15 +++++++++++++++ > drivers/vhost/vhost.c | 11 +++++++++++ > 2 files changed, 26 insertions(+) > > diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig > index b455d9ab6f3d..e5b9dcbf31b6 100644 > --- a/drivers/vhost/Kconfig > +++ b/drivers/vhost/Kconfig > @@ -95,3 +95,18 @@ config VHOST_CROSS_ENDIAN_LEGACY > If unsure, say "N". > > endif > + > +config VHOST_ENABLE_FORK_OWNER_IOCTL > + bool "Enable IOCTL VHOST_FORK_FROM_OWNER" > + default n > + help > + This option enables the IOCTL VHOST_FORK_FROM_OWNER, which allows > + userspace applications to modify the thread mode for vhost devices. > + > + By default, `CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL` is set to `n`, > + meaning the ioctl is disabled and any operation using this ioctl > + will fail. > + When the configuration is enabled (y), the ioctl becomes > + available, allowing users to set the mode if needed. > + > + If unsure, say "N". > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index fb0c7fb43f78..09e5e44dc516 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -2294,6 +2294,8 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > r = vhost_dev_set_owner(d); > goto done; > } > + > +#ifdef CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL > if (ioctl == VHOST_FORK_FROM_OWNER) { > u8 inherit_owner; > /*inherit_owner can only be modified before owner is set*/ > @@ -2313,6 +2315,15 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) > r = 0; > goto done; > } > + > +#else > + if (ioctl == VHOST_FORK_FROM_OWNER) { > + /* When CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL is 'n', return error */ > + r = -ENOTTY; > + goto done; > + } > +#endif > + > /* You must be the owner to do anything else */ > r = vhost_dev_check_owner(d); > if (r) > -- > 2.45.0 Do we need to change the default value of the inhert_owner? For example: #ifdef CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL inherit_owner = false; #else inherit_onwer = true; #endif ? Other patches look good to me. Thanks >
On Mon, Mar 03, 2025 at 01:52:06PM +0800, Jason Wang wrote: >On Sun, Mar 2, 2025 at 10:34 PM Cindy Lu <lulu@redhat.com> wrote: >> >> Introduce a new config knob `CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL`, >> to control the availability of the `VHOST_FORK_FROM_OWNER` ioctl. >> When CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL is set to n, the ioctl >> is disabled, and any attempt to use it will result in failure. >> >> Signed-off-by: Cindy Lu <lulu@redhat.com> >> --- >> drivers/vhost/Kconfig | 15 +++++++++++++++ >> drivers/vhost/vhost.c | 11 +++++++++++ >> 2 files changed, 26 insertions(+) >> >> diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig >> index b455d9ab6f3d..e5b9dcbf31b6 100644 >> --- a/drivers/vhost/Kconfig >> +++ b/drivers/vhost/Kconfig >> @@ -95,3 +95,18 @@ config VHOST_CROSS_ENDIAN_LEGACY >> If unsure, say "N". >> >> endif >> + >> +config VHOST_ENABLE_FORK_OWNER_IOCTL >> + bool "Enable IOCTL VHOST_FORK_FROM_OWNER" >> + default n >> + help >> + This option enables the IOCTL VHOST_FORK_FROM_OWNER, which allows >> + userspace applications to modify the thread mode for vhost devices. >> + >> + By default, `CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL` is set to `n`, >> + meaning the ioctl is disabled and any operation using this ioctl >> + will fail. >> + When the configuration is enabled (y), the ioctl becomes >> + available, allowing users to set the mode if needed. >> + >> + If unsure, say "N". >> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c >> index fb0c7fb43f78..09e5e44dc516 100644 >> --- a/drivers/vhost/vhost.c >> +++ b/drivers/vhost/vhost.c >> @@ -2294,6 +2294,8 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) >> r = vhost_dev_set_owner(d); >> goto done; >> } >> + >> +#ifdef CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL >> if (ioctl == VHOST_FORK_FROM_OWNER) { >> u8 inherit_owner; >> /*inherit_owner can only be modified before owner is set*/ >> @@ -2313,6 +2315,15 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) >> r = 0; >> goto done; >> } >> + nit: this empyt line is not needed >> +#else >> + if (ioctl == VHOST_FORK_FROM_OWNER) { >> + /* When CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL is 'n', return error */ >> + r = -ENOTTY; >> + goto done; >> + } >> +#endif >> + >> /* You must be the owner to do anything else */ >> r = vhost_dev_check_owner(d); >> if (r) >> -- >> 2.45.0 > >Do we need to change the default value of the inhert_owner? For example: > >#ifdef CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL >inherit_owner = false; >#else >inherit_onwer = true; >#endif > >? I'm not sure about this honestly, the user space has no way to figure out the default value and still has to do the IOCTL. So IMHO better to have a default value that is independent of the kernel configuration and consistent with the current behavior. Thanks, Stefano > >Other patches look good to me. > >Thanks > >> >
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index b455d9ab6f3d..e5b9dcbf31b6 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -95,3 +95,18 @@ config VHOST_CROSS_ENDIAN_LEGACY If unsure, say "N". endif + +config VHOST_ENABLE_FORK_OWNER_IOCTL + bool "Enable IOCTL VHOST_FORK_FROM_OWNER" + default n + help + This option enables the IOCTL VHOST_FORK_FROM_OWNER, which allows + userspace applications to modify the thread mode for vhost devices. + + By default, `CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL` is set to `n`, + meaning the ioctl is disabled and any operation using this ioctl + will fail. + When the configuration is enabled (y), the ioctl becomes + available, allowing users to set the mode if needed. + + If unsure, say "N". diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index fb0c7fb43f78..09e5e44dc516 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2294,6 +2294,8 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) r = vhost_dev_set_owner(d); goto done; } + +#ifdef CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL if (ioctl == VHOST_FORK_FROM_OWNER) { u8 inherit_owner; /*inherit_owner can only be modified before owner is set*/ @@ -2313,6 +2315,15 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) r = 0; goto done; } + +#else + if (ioctl == VHOST_FORK_FROM_OWNER) { + /* When CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL is 'n', return error */ + r = -ENOTTY; + goto done; + } +#endif + /* You must be the owner to do anything else */ r = vhost_dev_check_owner(d); if (r)
Introduce a new config knob `CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL`, to control the availability of the `VHOST_FORK_FROM_OWNER` ioctl. When CONFIG_VHOST_ENABLE_FORK_OWNER_IOCTL is set to n, the ioctl is disabled, and any attempt to use it will result in failure. Signed-off-by: Cindy Lu <lulu@redhat.com> --- drivers/vhost/Kconfig | 15 +++++++++++++++ drivers/vhost/vhost.c | 11 +++++++++++ 2 files changed, 26 insertions(+)