Hi Palmer,
The warning is from a clang problem.
drivers/net/wireguard/queueing.c:
static void __wg_prev_queue_enqueue(struct prev_queue *queue, struct
sk_buff *skb)
{
WRITE_ONCE(NEXT(skb), NULL);
WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
}
The queue->head is 64bit pointer size.
#define __xchg_relaxed(ptr, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
case 2: { \
... Clang shouldn't give warning from here, because code won't enter the path.
break; \
} \
case 4: \
...
break; \
case 8: \
... The case would enter this path.
break; \
default: \
BUILD_BUG(); \
} \
__ret; \
})
On Thu, Jul 28, 2022 at 8:05 AM kernel test robot <lkp@xxxxxxxxx> wrote:
>
> Hi,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on arnd-asm-generic/master]
> [also build test WARNING on linus/master v5.19-rc8 next-20220727]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
>
> url: https://github.com/intel-lab-lkp/linux/commits/guoren-kernel-org/arch-Add-qspinlock-support-with-combo-style/20220724-202743
> base: https://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic.git master
> config: riscv-randconfig-r026-20220727 (https://download.01.org/0day-ci/archive/20220728/202207280822.VHS6qieH-lkp@xxxxxxxxx/config)
> compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 8dfaecc4c24494337933aff9d9166486ca0949f1)
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # install riscv cross compiling tool for clang build
> # apt-get install binutils-riscv64-linux-gnu
> # https://github.com/intel-lab-lkp/linux/commit/980c0acb7f432777e3473ab9a5696044e03b3f3d
> git remote add linux-review https://github.com/intel-lab-lkp/linux
> git fetch --no-tags linux-review guoren-kernel-org/arch-Add-qspinlock-support-with-combo-style/20220724-202743
> git checkout 980c0acb7f432777e3473ab9a5696044e03b3f3d
> # save the config file
> mkdir build_dir && cp config build_dir/.config
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash drivers/net/wireguard/
>
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> All warnings (new ones prefixed by >>):
>
> In file included from drivers/net/wireguard/queueing.c:6:
> In file included from drivers/net/wireguard/queueing.h:9:
> In file included from drivers/net/wireguard/peer.h:9:
> In file included from drivers/net/wireguard/device.h:9:
> In file included from drivers/net/wireguard/noise.h:8:
> In file included from drivers/net/wireguard/messages.h:10:
> In file included from include/crypto/chacha20poly1305.h:10:
> In file included from include/linux/scatterlist.h:9:
> In file included from arch/riscv/include/asm/io.h:136:
> include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
> val = __raw_readb(PCI_IOBASE + addr);
> ~~~~~~~~~~ ^
> include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
> val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
> ~~~~~~~~~~ ^
> include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
> #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
> ^
> In file included from drivers/net/wireguard/queueing.c:6:
> In file included from drivers/net/wireguard/queueing.h:9:
> In file included from drivers/net/wireguard/peer.h:9:
> In file included from drivers/net/wireguard/device.h:9:
> In file included from drivers/net/wireguard/noise.h:8:
> In file included from drivers/net/wireguard/messages.h:10:
> In file included from include/crypto/chacha20poly1305.h:10:
> In file included from include/linux/scatterlist.h:9:
> In file included from arch/riscv/include/asm/io.h:136:
> include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
> val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
> ~~~~~~~~~~ ^
> include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
> #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
> ^
> In file included from drivers/net/wireguard/queueing.c:6:
> In file included from drivers/net/wireguard/queueing.h:9:
> In file included from drivers/net/wireguard/peer.h:9:
> In file included from drivers/net/wireguard/device.h:9:
> In file included from drivers/net/wireguard/noise.h:8:
> In file included from drivers/net/wireguard/messages.h:10:
> In file included from include/crypto/chacha20poly1305.h:10:
> In file included from include/linux/scatterlist.h:9:
> In file included from arch/riscv/include/asm/io.h:136:
> include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
> __raw_writeb(value, PCI_IOBASE + addr);
> ~~~~~~~~~~ ^
> include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
> __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
> ~~~~~~~~~~ ^
> include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
> __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
> ~~~~~~~~~~ ^
> include/asm-generic/io.h:1107:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
> return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
> ~~~~~~~~~~ ^
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to smaller integer type 'u32' (aka 'unsigned int') from 'typeof (_x_)' (aka 'struct sk_buff *') [-Wpointer-to-int-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^~~~~~~~~~~~~~~~~~
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ^~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ^~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to 'typeof (*((__ai_ptr)))' (aka 'struct sk_buff *') from smaller integer type 'unsigned int' [-Wint-to-pointer-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to smaller integer type 'u32' (aka 'unsigned int') from 'typeof (_x_)' (aka 'struct sk_buff *') [-Wpointer-to-int-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^~~~~~~~~~~~~~~~~~
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ^~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ^~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to 'typeof (*((__ai_ptr)))' (aka 'struct sk_buff *') from smaller integer type 'unsigned int' [-Wint-to-pointer-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to smaller integer type 'u32' (aka 'unsigned int') from 'typeof (_x_)' (aka 'struct sk_buff *') [-Wpointer-to-int-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^~~~~~~~~~~~~~~~~~
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ^~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ^~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to 'typeof (*((__ai_ptr)))' (aka 'struct sk_buff *') from smaller integer type 'unsigned int' [-Wint-to-pointer-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to smaller integer type 'u32' (aka 'unsigned int') from 'typeof (_x_)' (aka 'struct sk_buff *') [-Wpointer-to-int-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^~~~~~~~~~~~~~~~~~
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ^~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ^~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to 'typeof (*((__ai_ptr)))' (aka 'struct sk_buff *') from smaller integer type 'unsigned int' [-Wint-to-pointer-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^
> note: (skipping 7 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to smaller integer type 'u32' (aka 'unsigned int') from 'typeof (_x_)' (aka 'struct sk_buff *') [-Wpointer-to-int-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^~~~~~~~~~~~~~~~~~
> note: (skipping 6 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ^~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ^~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to 'typeof (*((__ai_ptr)))' (aka 'struct sk_buff *') from smaller integer type 'unsigned int' [-Wint-to-pointer-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^
> note: (skipping 6 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> include/linux/compiler_types.h:352:22: note: expanded from macro 'compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
> ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:340:23: note: expanded from macro '_compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/compiler_types.h:332:9: note: expanded from macro '__compiletime_assert'
> if (!(condition)) \
> ^~~~~~~~~
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to smaller integer type 'u32' (aka 'unsigned int') from 'typeof (_x_)' (aka 'struct sk_buff *') [-Wpointer-to-int-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^~~~~~~~~~~~~~~~~~
> note: (skipping 3 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> drivers/net/wireguard/queueing.c:49:21: note: expanded from macro 'NEXT'
> #define NEXT(skb) ((skb)->prev)
> ^~~
> include/asm-generic/rwonce.h:61:15: note: expanded from macro 'WRITE_ONCE'
> __WRITE_ONCE(x, val); \
> ^
> include/asm-generic/rwonce.h:55:20: note: expanded from macro '__WRITE_ONCE'
> *(volatile typeof(x) *)&(x) = (val); \
> ^
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to 'typeof (*((__ai_ptr)))' (aka 'struct sk_buff *') from smaller integer type 'unsigned int' [-Wint-to-pointer-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^
> note: (skipping 3 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> drivers/net/wireguard/queueing.c:49:21: note: expanded from macro 'NEXT'
> #define NEXT(skb) ((skb)->prev)
> ^
> include/asm-generic/rwonce.h:61:15: note: expanded from macro 'WRITE_ONCE'
> __WRITE_ONCE(x, val); \
> ~~~~~~~~~~~~~^~~~~~~
> include/asm-generic/rwonce.h:55:20: note: expanded from macro '__WRITE_ONCE'
> *(volatile typeof(x) *)&(x) = (val); \
> ^
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to smaller integer type 'u32' (aka 'unsigned int') from 'typeof (_x_)' (aka 'struct sk_buff *') [-Wpointer-to-int-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^~~~~~~~~~~~~~~~~~
> note: (skipping 3 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> drivers/net/wireguard/queueing.c:49:21: note: expanded from macro 'NEXT'
> #define NEXT(skb) ((skb)->prev)
> ^~~
> include/asm-generic/rwonce.h:61:15: note: expanded from macro 'WRITE_ONCE'
> __WRITE_ONCE(x, val); \
> ^
> include/asm-generic/rwonce.h:55:27: note: expanded from macro '__WRITE_ONCE'
> *(volatile typeof(x) *)&(x) = (val); \
> ^
> >> drivers/net/wireguard/queueing.c:68:18: warning: cast to 'typeof (*((__ai_ptr)))' (aka 'struct sk_buff *') from smaller integer type 'unsigned int' [-Wint-to-pointer-cast]
> WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> include/linux/atomic/atomic-instrumented.h:1901:2: note: expanded from macro 'xchg_release'
> arch_xchg_release(__ai_ptr, __VA_ARGS__); \
> ^
> include/linux/atomic/atomic-arch-fallback.h:24:2: note: expanded from macro 'arch_xchg_release'
> __atomic_op_release(arch_xchg, __VA_ARGS__)
> ^
> include/linux/atomic.h:68:2: note: expanded from macro '__atomic_op_release'
> op##_relaxed(args); \
> ^
> note: (skipping 3 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
> drivers/net/wireguard/queueing.c:49:21: note: expanded from macro 'NEXT'
> #define NEXT(skb) ((skb)->prev)
> ^
> include/asm-generic/rwonce.h:61:15: note: expanded from macro 'WRITE_ONCE'
> __WRITE_ONCE(x, val); \
> ~~~~~~~~~~~~~^~~~~~~
> include/asm-generic/rwonce.h:55:27: note: expanded from macro '__WRITE_ONCE'
> *(volatile typeof(x) *)&(x) = (val); \
> ^
> 21 warnings generated.
>
>
> vim +68 drivers/net/wireguard/queueing.c
>
> 8b5553ace83cced7 Jason A. Donenfeld 2021-02-22 64
> 8b5553ace83cced7 Jason A. Donenfeld 2021-02-22 65 static void __wg_prev_queue_enqueue(struct prev_queue *queue, struct sk_buff *skb)
> 8b5553ace83cced7 Jason A. Donenfeld 2021-02-22 66 {
> 8b5553ace83cced7 Jason A. Donenfeld 2021-02-22 67 WRITE_ONCE(NEXT(skb), NULL);
> 8b5553ace83cced7 Jason A. Donenfeld 2021-02-22 @68 WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb);
> 8b5553ace83cced7 Jason A. Donenfeld 2021-02-22 69 }
> 8b5553ace83cced7 Jason A. Donenfeld 2021-02-22 70
>
> --
> 0-DAY CI Kernel Test Service
> https://01.org/lkp
--
Best Regards
Guo Ren
