* Re: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
2023-10-02 17:53 [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT Nathan Chancellor
@ 2023-10-02 17:57 ` Nick Desaulniers
2023-10-03 4:17 ` Agarwal, Nikhil
` (2 subsequent siblings)
3 siblings, 0 replies; 8+ messages in thread
From: Nick Desaulniers @ 2023-10-02 17:57 UTC (permalink / raw)
To: Nathan Chancellor
Cc: nipun.gupta, nikhil.agarwal, alex.williamson, trix,
shubham.rohila, kvm, llvm, patches
On Mon, Oct 2, 2023 at 10:53 AM Nathan Chancellor <nathan@kernel.org> wrote:
>
> When building with clang, there is a warning (or error with
> CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
> vfio_cdx_bm_ctrl():
>
> drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^ ~
> drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> 1 error generated.
>
> Add the parentheses as suggested in the first note, which is clearly
> what was intended here.
>
> Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
> Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support")
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Thanks for the patch!
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
> ---
> drivers/vfio/cdx/main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/cdx/main.c b/drivers/vfio/cdx/main.c
> index a437630be354..a63744302b5e 100644
> --- a/drivers/vfio/cdx/main.c
> +++ b/drivers/vfio/cdx/main.c
> @@ -74,7 +74,7 @@ static int vfio_cdx_bm_ctrl(struct vfio_device *core_vdev, u32 flags,
> struct vfio_device_feature_bus_master ops;
> int ret;
>
> - if (!vdev->flags & BME_SUPPORT)
> + if (!(vdev->flags & BME_SUPPORT))
> return -ENOTTY;
>
> ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
>
> ---
> base-commit: fcb2f2ed4a80cfe383d87da75caba958516507e9
> change-id: 20231002-vfio-cdx-logical-not-parentheses-aca8fbd6b278
>
> Best regards,
> --
> Nathan Chancellor <nathan@kernel.org>
>
>
--
Thanks,
~Nick Desaulniers
^ permalink raw reply [flat|nested] 8+ messages in thread* RE: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
2023-10-02 17:53 [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT Nathan Chancellor
2023-10-02 17:57 ` Nick Desaulniers
@ 2023-10-03 4:17 ` Agarwal, Nikhil
2023-10-03 7:40 ` Philippe Mathieu-Daudé
2023-10-03 18:01 ` Alex Williamson
3 siblings, 0 replies; 8+ messages in thread
From: Agarwal, Nikhil @ 2023-10-03 4:17 UTC (permalink / raw)
To: Nathan Chancellor, Gupta, Nipun, alex.williamson@redhat.com
Cc: ndesaulniers@google.com, trix@redhat.com, Rohila, Shubham,
kvm@vger.kernel.org, llvm@lists.linux.dev,
patches@lists.linux.dev
[AMD Official Use Only - General]
> -----Original Message-----
> From: Nathan Chancellor <nathan@kernel.org>
> Sent: Monday, October 2, 2023 11:23 PM
> To: Gupta, Nipun <Nipun.Gupta@amd.com>; Agarwal, Nikhil
> <nikhil.agarwal@amd.com>; alex.williamson@redhat.com
> Cc: ndesaulniers@google.com; trix@redhat.com; Rohila, Shubham
> <shubham.rohila@amd.com>; kvm@vger.kernel.org; llvm@lists.linux.dev;
> patches@lists.linux.dev; Nathan Chancellor <nathan@kernel.org>
> Subject: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression
> and logical NOT
>
> When building with clang, there is a warning (or error with
> CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
> vfio_cdx_bm_ctrl():
>
> drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand
> side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^ ~
> drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate
> the bitwise operator first
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side
> expression to silence this warning
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> 1 error generated.
>
> Add the parentheses as suggested in the first note, which is clearly what was
> intended here.
>
> Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
> Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support")
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> ---
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
2023-10-02 17:53 [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT Nathan Chancellor
2023-10-02 17:57 ` Nick Desaulniers
2023-10-03 4:17 ` Agarwal, Nikhil
@ 2023-10-03 7:40 ` Philippe Mathieu-Daudé
2023-10-03 15:27 ` Nathan Chancellor
2023-10-03 18:01 ` Alex Williamson
3 siblings, 1 reply; 8+ messages in thread
From: Philippe Mathieu-Daudé @ 2023-10-03 7:40 UTC (permalink / raw)
To: Nathan Chancellor, nipun.gupta, nikhil.agarwal, alex.williamson
Cc: ndesaulniers, trix, shubham.rohila, kvm, llvm, patches
Hi Nathan,
On 2/10/23 19:53, Nathan Chancellor wrote:
> When building with clang, there is a warning (or error with
> CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
> vfio_cdx_bm_ctrl():
>
> drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^ ~
> drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> 1 error generated.
>
> Add the parentheses as suggested in the first note, which is clearly
> what was intended here.
>
> Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
> Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support")
My current /master points to commit ce36c8b14987 which doesn't include
8a97ab9b8b31, so maybe this can be squashed / reordered in the VFIO tree
(where I assume this commit is). That said, the fix is correct, so:
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Regards,
Phil.
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> ---
> drivers/vfio/cdx/main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/cdx/main.c b/drivers/vfio/cdx/main.c
> index a437630be354..a63744302b5e 100644
> --- a/drivers/vfio/cdx/main.c
> +++ b/drivers/vfio/cdx/main.c
> @@ -74,7 +74,7 @@ static int vfio_cdx_bm_ctrl(struct vfio_device *core_vdev, u32 flags,
> struct vfio_device_feature_bus_master ops;
> int ret;
>
> - if (!vdev->flags & BME_SUPPORT)
> + if (!(vdev->flags & BME_SUPPORT))
> return -ENOTTY;
>
> ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
>
> ---
> base-commit: fcb2f2ed4a80cfe383d87da75caba958516507e9
> change-id: 20231002-vfio-cdx-logical-not-parentheses-aca8fbd6b278
>
> Best regards,
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
2023-10-03 7:40 ` Philippe Mathieu-Daudé
@ 2023-10-03 15:27 ` Nathan Chancellor
2023-10-03 17:20 ` Alex Williamson
0 siblings, 1 reply; 8+ messages in thread
From: Nathan Chancellor @ 2023-10-03 15:27 UTC (permalink / raw)
To: Philippe Mathieu-Daudé
Cc: nipun.gupta, nikhil.agarwal, alex.williamson, ndesaulniers, trix,
shubham.rohila, kvm, llvm, patches
On Tue, Oct 03, 2023 at 09:40:02AM +0200, Philippe Mathieu-Daudé wrote:
> Hi Nathan,
>
> On 2/10/23 19:53, Nathan Chancellor wrote:
> > When building with clang, there is a warning (or error with
> > CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
> > vfio_cdx_bm_ctrl():
> >
> > drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
> > 77 | if (!vdev->flags & BME_SUPPORT)
> > | ^ ~
> > drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first
> > 77 | if (!vdev->flags & BME_SUPPORT)
> > | ^
> > | ( )
> > drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning
> > 77 | if (!vdev->flags & BME_SUPPORT)
> > | ^
> > | ( )
> > 1 error generated.
> >
> > Add the parentheses as suggested in the first note, which is clearly
> > what was intended here.
> >
> > Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
> > Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support")
>
> My current /master points to commit ce36c8b14987 which doesn't include
> 8a97ab9b8b31, so maybe this can be squashed / reordered in the VFIO tree
> (where I assume this commit is). That said, the fix is correct, so:
Yes, this is a -next only issue at the moment and I don't mind this
change being squashed into the original if Alex rebases his tree (some
maintainers don't).
> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Thanks a lot for taking a look!
Cheers,
Nathan
> > Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> > ---
> > drivers/vfio/cdx/main.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/vfio/cdx/main.c b/drivers/vfio/cdx/main.c
> > index a437630be354..a63744302b5e 100644
> > --- a/drivers/vfio/cdx/main.c
> > +++ b/drivers/vfio/cdx/main.c
> > @@ -74,7 +74,7 @@ static int vfio_cdx_bm_ctrl(struct vfio_device *core_vdev, u32 flags,
> > struct vfio_device_feature_bus_master ops;
> > int ret;
> > - if (!vdev->flags & BME_SUPPORT)
> > + if (!(vdev->flags & BME_SUPPORT))
> > return -ENOTTY;
> > ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
> >
> > ---
> > base-commit: fcb2f2ed4a80cfe383d87da75caba958516507e9
> > change-id: 20231002-vfio-cdx-logical-not-parentheses-aca8fbd6b278
> >
> > Best regards,
>
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
2023-10-03 15:27 ` Nathan Chancellor
@ 2023-10-03 17:20 ` Alex Williamson
2023-10-04 6:48 ` Philippe Mathieu-Daudé
0 siblings, 1 reply; 8+ messages in thread
From: Alex Williamson @ 2023-10-03 17:20 UTC (permalink / raw)
To: Nathan Chancellor
Cc: Philippe Mathieu-Daudé, nipun.gupta, nikhil.agarwal,
ndesaulniers, trix, shubham.rohila, kvm, llvm, patches
On Tue, 3 Oct 2023 08:27:39 -0700
Nathan Chancellor <nathan@kernel.org> wrote:
> On Tue, Oct 03, 2023 at 09:40:02AM +0200, Philippe Mathieu-Daudé wrote:
> > Hi Nathan,
> >
> > On 2/10/23 19:53, Nathan Chancellor wrote:
> > > When building with clang, there is a warning (or error with
> > > CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
> > > vfio_cdx_bm_ctrl():
> > >
> > > drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
> > > 77 | if (!vdev->flags & BME_SUPPORT)
> > > | ^ ~
> > > drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first
> > > 77 | if (!vdev->flags & BME_SUPPORT)
> > > | ^
> > > | ( )
> > > drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning
> > > 77 | if (!vdev->flags & BME_SUPPORT)
> > > | ^
> > > | ( )
> > > 1 error generated.
> > >
> > > Add the parentheses as suggested in the first note, which is clearly
> > > what was intended here.
> > >
> > > Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
> > > Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support")
> >
> > My current /master points to commit ce36c8b14987 which doesn't include
> > 8a97ab9b8b31, so maybe this can be squashed / reordered in the VFIO tree
> > (where I assume this commit is). That said, the fix is correct, so:
>
> Yes, this is a -next only issue at the moment and I don't mind this
> change being squashed into the original if Alex rebases his tree (some
> maintainers don't).
Right, where practical we try not to change commit hashes once
something has been included into linux-next, preferring to layer fixes
or even reverts, but occasionally something will come up where it makes
sense to rebase. This is not such a case :) Thanks,
Alex
> > Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>
> Thanks a lot for taking a look!
>
> Cheers,
> Nathan
>
> > > Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> > > ---
> > > drivers/vfio/cdx/main.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/vfio/cdx/main.c b/drivers/vfio/cdx/main.c
> > > index a437630be354..a63744302b5e 100644
> > > --- a/drivers/vfio/cdx/main.c
> > > +++ b/drivers/vfio/cdx/main.c
> > > @@ -74,7 +74,7 @@ static int vfio_cdx_bm_ctrl(struct vfio_device *core_vdev, u32 flags,
> > > struct vfio_device_feature_bus_master ops;
> > > int ret;
> > > - if (!vdev->flags & BME_SUPPORT)
> > > + if (!(vdev->flags & BME_SUPPORT))
> > > return -ENOTTY;
> > > ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
> > >
> > > ---
> > > base-commit: fcb2f2ed4a80cfe383d87da75caba958516507e9
> > > change-id: 20231002-vfio-cdx-logical-not-parentheses-aca8fbd6b278
> > >
> > > Best regards,
> >
>
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
2023-10-03 17:20 ` Alex Williamson
@ 2023-10-04 6:48 ` Philippe Mathieu-Daudé
0 siblings, 0 replies; 8+ messages in thread
From: Philippe Mathieu-Daudé @ 2023-10-04 6:48 UTC (permalink / raw)
To: Alex Williamson, Nathan Chancellor
Cc: nipun.gupta, nikhil.agarwal, ndesaulniers, trix, shubham.rohila,
kvm, llvm, patches
On 3/10/23 19:20, Alex Williamson wrote:
> On Tue, 3 Oct 2023 08:27:39 -0700
> Nathan Chancellor <nathan@kernel.org> wrote:
>
>> On Tue, Oct 03, 2023 at 09:40:02AM +0200, Philippe Mathieu-Daudé wrote:
>>> Hi Nathan,
>>>
>>> On 2/10/23 19:53, Nathan Chancellor wrote:
>>>> When building with clang, there is a warning (or error with
>>>> CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
>>>> vfio_cdx_bm_ctrl():
>>>>
>>>> drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
>>>> 77 | if (!vdev->flags & BME_SUPPORT)
>>>> | ^ ~
>>>> drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first
>>>> 77 | if (!vdev->flags & BME_SUPPORT)
>>>> | ^
>>>> | ( )
>>>> drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning
>>>> 77 | if (!vdev->flags & BME_SUPPORT)
>>>> | ^
>>>> | ( )
>>>> 1 error generated.
>>>>
>>>> Add the parentheses as suggested in the first note, which is clearly
>>>> what was intended here.
>>>>
>>>> Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
>>>> Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support")
>>>
>>> My current /master points to commit ce36c8b14987 which doesn't include
>>> 8a97ab9b8b31, so maybe this can be squashed / reordered in the VFIO tree
>>> (where I assume this commit is). That said, the fix is correct, so:
>>
>> Yes, this is a -next only issue at the moment and I don't mind this
>> change being squashed into the original if Alex rebases his tree (some
>> maintainers don't).
>
> Right, where practical we try not to change commit hashes once
> something has been included into linux-next, preferring to layer fixes
> or even reverts, but occasionally something will come up where it makes
> sense to rebase. This is not such a case :) Thanks,
Got it, thanks!
>
> Alex
>
>>> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>>
>> Thanks a lot for taking a look!
>>
>> Cheers,
>> Nathan
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT
2023-10-02 17:53 [PATCH] vfio/cdx: Add parentheses between bitwise AND expression and logical NOT Nathan Chancellor
` (2 preceding siblings ...)
2023-10-03 7:40 ` Philippe Mathieu-Daudé
@ 2023-10-03 18:01 ` Alex Williamson
3 siblings, 0 replies; 8+ messages in thread
From: Alex Williamson @ 2023-10-03 18:01 UTC (permalink / raw)
To: Nathan Chancellor
Cc: nipun.gupta, nikhil.agarwal, ndesaulniers, trix, shubham.rohila,
kvm, llvm, patches
On Mon, 02 Oct 2023 10:53:13 -0700
Nathan Chancellor <nathan@kernel.org> wrote:
> When building with clang, there is a warning (or error with
> CONFIG_WERROR=y) due to a bitwise AND and logical NOT in
> vfio_cdx_bm_ctrl():
>
> drivers/vfio/cdx/main.c:77:6: error: logical not is only applied to the left hand side of this bitwise operator [-Werror,-Wlogical-not-parentheses]
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^ ~
> drivers/vfio/cdx/main.c:77:6: note: add parentheses after the '!' to evaluate the bitwise operator first
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> drivers/vfio/cdx/main.c:77:6: note: add parentheses around left hand side expression to silence this warning
> 77 | if (!vdev->flags & BME_SUPPORT)
> | ^
> | ( )
> 1 error generated.
>
> Add the parentheses as suggested in the first note, which is clearly
> what was intended here.
>
> Closes: https://github.com/ClangBuiltLinux/linux/issues/1939
> Fixes: 8a97ab9b8b31 ("vfio-cdx: add bus mastering device feature support")
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> ---
> drivers/vfio/cdx/main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/cdx/main.c b/drivers/vfio/cdx/main.c
> index a437630be354..a63744302b5e 100644
> --- a/drivers/vfio/cdx/main.c
> +++ b/drivers/vfio/cdx/main.c
> @@ -74,7 +74,7 @@ static int vfio_cdx_bm_ctrl(struct vfio_device *core_vdev, u32 flags,
> struct vfio_device_feature_bus_master ops;
> int ret;
>
> - if (!vdev->flags & BME_SUPPORT)
> + if (!(vdev->flags & BME_SUPPORT))
> return -ENOTTY;
>
> ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
>
> ---
> base-commit: fcb2f2ed4a80cfe383d87da75caba958516507e9
> change-id: 20231002-vfio-cdx-logical-not-parentheses-aca8fbd6b278
>
> Best regards,
Applied to vfio next branch for v6.7. Thanks!
Alex
^ permalink raw reply [flat|nested] 8+ messages in thread