Re: [PATCH v2 2/2] tools/virtio: fix build caused by virtio_ring changes

Shunsuke Mie
2023-04-11T03:17:59Z

On 2023/04/11 3:40, Greg Kroah-Hartman wrote:
> On Mon, Apr 10, 2023 at 08:00:33AM -0400, Michael S. Tsirkin wrote:
>> On Mon, Apr 10, 2023 at 08:28:45PM +0900, Shunsuke Mie wrote:
>>> Fix the build dependency for virtio_test. The virtio_ring that is used from
>>> the test requires container_of_const(). Change to use container_of.h kernel
>>> header directly and adapt related codes.
>>>
>>> Signed-off-by: Shunsuke Mie <mie@igel.co.jp>
>> This is only for next right? That's where container_of_const
>> things are I think ...
> container_of_const() is in 6.2.
>
>
>>> ---
>>> tools/include/linux/types.h | 1 -
>>> tools/virtio/linux/compiler.h | 2 ++
>>> tools/virtio/linux/kernel.h | 5 +----
>>> tools/virtio/linux/module.h | 1 -
>>> tools/virtio/linux/uaccess.h | 11 ++---------
>>> 5 files changed, 5 insertions(+), 15 deletions(-)
>>>
>>> diff --git a/tools/include/linux/types.h b/tools/include/linux/types.h
>>> index 051fdeaf2670..f1896b70a8e5 100644
>>> --- a/tools/include/linux/types.h
>>> +++ b/tools/include/linux/types.h
>>> @@ -49,7 +49,6 @@ typedef __s8 s8;
>>> #endif
>>>
>>> #define __force
>>> -#define __user
> Why is this needed?
>
>>> #define __must_check
>>> #define __cold
>>>
>>> diff --git a/tools/virtio/linux/compiler.h b/tools/virtio/linux/compiler.h
>>> index 2c51bccb97bb..1f3a15b954b9 100644
>>> --- a/tools/virtio/linux/compiler.h
>>> +++ b/tools/virtio/linux/compiler.h
>>> @@ -2,6 +2,8 @@
>>> #ifndef LINUX_COMPILER_H
>>> #define LINUX_COMPILER_H
>>>
>>> +#include "../../../include/linux/compiler_types.h"
> While I understand your need to not want to duplicate code, what in the
> world is this doing? Why not use the in-kernel compiler.h instead? Why
> are you copying loads of .h files into tools/virtio/? What is this for
> and why not just use the real files so you don't have to even attempt to
> try to keep things in sync (hint, they will always be out of sync.)
>
>>> +
>>> #define WRITE_ONCE(var, val) \
>>> (*((volatile typeof(val) *)(&(var))) = (val))
>>>
>>> diff --git a/tools/virtio/linux/kernel.h b/tools/virtio/linux/kernel.h
>>> index 8b877167933d..6702008f7f5c 100644
>>> --- a/tools/virtio/linux/kernel.h
>>> +++ b/tools/virtio/linux/kernel.h
>>> @@ -10,6 +10,7 @@
>>> #include <stdarg.h>
>>>
>>> #include <linux/compiler.h>
>>> +#include "../../../include/linux/container_of.h"
> Either do this for all .h files, or not, don't pick and choose.
>
>
>
>>> #include <linux/log2.h>
>>> #include <linux/types.h>
>>> #include <linux/overflow.h>
>>> @@ -107,10 +108,6 @@ static inline void free_page(unsigned long addr)
>>> free((void *)addr);
>>> }
>>>
>>> -#define container_of(ptr, type, member) ({ \
>>> - const typeof( ((type *)0)->member ) *__mptr = (ptr); \
>>> - (type *)( (char *)__mptr - offsetof(type,member) );})
>>> -
>>> # ifndef likely
>>> # define likely(x) (__builtin_expect(!!(x), 1))
>>> # endif
>>> diff --git a/tools/virtio/linux/module.h b/tools/virtio/linux/module.h
>>> index 9dfa96fea2b2..5cf39167d47a 100644
>>> --- a/tools/virtio/linux/module.h
>>> +++ b/tools/virtio/linux/module.h
>>> @@ -4,4 +4,3 @@
>>> #define MODULE_LICENSE(__MODULE_LICENSE_value) \
>>> static __attribute__((unused)) const char *__MODULE_LICENSE_name = \
>>> __MODULE_LICENSE_value
>>> -
> This change has nothing to do with what you said was happening in this
> patch :(
>
> Please be more careful.
>
>>> diff --git a/tools/virtio/linux/uaccess.h b/tools/virtio/linux/uaccess.h
>>> index 991dfb263998..cde2c344b260 100644
>>> --- a/tools/virtio/linux/uaccess.h
>>> +++ b/tools/virtio/linux/uaccess.h
>>> @@ -6,15 +6,10 @@
>>>
>>> extern void *__user_addr_min, *__user_addr_max;
>>>
>>> -static inline void __chk_user_ptr(const volatile void *p, size_t size)
>>> -{
>>> - assert(p >= __user_addr_min && p + size <= __user_addr_max);
>>> -}
>>> -
> What does this function have to do with container_of()?
>
>
>>> #define put_user(x, ptr) \
>>> ({ \
>>> typeof(ptr) __pu_ptr = (ptr); \
>>> - __chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr)); \
>>> + __chk_user_ptr(__pu_ptr); \
> Why are you trying to duplicate in-kernel .h files?
>
> This all doesn't look ok, sorry.
>
> greg k-h

Thank you. I'll modify problems you commented, but we have to discuss
the design of tools/virtio.

Best regards,

Shunsuke.