From 9776e3861e0e30330f6c8ca9c30348f336d24b1c Mon Sep 17 00:00:00 2001 From: Luc Van Oostenryck Date: Sun, 5 Jun 2022 18:07:38 +0200 Subject: [PATCH] ia64: fix sparse warnings with cmpxchg() & xchg() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit On IA64, new sparse's warnings where issued after fixing some __rcu annotations in kernel/bpf/. These new warnings are false positives and appear on IA64 because on this architecture, the macros for cmpxchg() and xchg() make casts that ignore sparse annotations. This patch contains the minimal patch to fix this issue: adding a missing cast and some missing '__force'. Link: https://lore.kernel.org/r/20220601120013.bq5a3ynbkc3hngm5@mail Link: https://lkml.kernel.org/r/20220605160738.79736-1-luc.vanoostenryck@gmail.com Signed-off-by: Luc Van Oostenryck Reported-by: kernel test robot Acked-by: Paul E. McKenney Acked-by: Toke Høiland-Jørgensen Cc: Arnd Bergmann Signed-off-by: Andrew Morton --- arch/ia64/include/uapi/asm/cmpxchg.h | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/arch/ia64/include/uapi/asm/cmpxchg.h b/arch/ia64/include/uapi/asm/cmpxchg.h index 2c2f3cfeaa77..ca2e02685343 100644 --- a/arch/ia64/include/uapi/asm/cmpxchg.h +++ b/arch/ia64/include/uapi/asm/cmpxchg.h @@ -33,24 +33,24 @@ extern void ia64_xchg_called_with_bad_pointer(void); \ switch (size) { \ case 1: \ - __xchg_result = ia64_xchg1((__u8 *)ptr, x); \ + __xchg_result = ia64_xchg1((__u8 __force *)ptr, x); \ break; \ \ case 2: \ - __xchg_result = ia64_xchg2((__u16 *)ptr, x); \ + __xchg_result = ia64_xchg2((__u16 __force *)ptr, x); \ break; \ \ case 4: \ - __xchg_result = ia64_xchg4((__u32 *)ptr, x); \ + __xchg_result = ia64_xchg4((__u32 __force *)ptr, x); \ break; \ \ case 8: \ - __xchg_result = ia64_xchg8((__u64 *)ptr, x); \ + __xchg_result = ia64_xchg8((__u64 __force *)ptr, x); \ break; \ default: \ ia64_xchg_called_with_bad_pointer(); \ } \ - __xchg_result; \ + (__typeof__ (*(ptr)) __force) __xchg_result; \ }) #ifndef __KERNEL__ @@ -76,42 +76,42 @@ extern long ia64_cmpxchg_called_with_bad_pointer(void); \ switch (size) { \ case 1: \ - _o_ = (__u8) (long) (old); \ + _o_ = (__u8) (long __force) (old); \ break; \ case 2: \ - _o_ = (__u16) (long) (old); \ + _o_ = (__u16) (long __force) (old); \ break; \ case 4: \ - _o_ = (__u32) (long) (old); \ + _o_ = (__u32) (long __force) (old); \ break; \ case 8: \ - _o_ = (__u64) (long) (old); \ + _o_ = (__u64) (long __force) (old); \ break; \ default: \ break; \ } \ switch (size) { \ case 1: \ - _r_ = ia64_cmpxchg1_##sem((__u8 *) ptr, new, _o_); \ + _r_ = ia64_cmpxchg1_##sem((__u8 __force *) ptr, new, _o_); \ break; \ \ case 2: \ - _r_ = ia64_cmpxchg2_##sem((__u16 *) ptr, new, _o_); \ + _r_ = ia64_cmpxchg2_##sem((__u16 __force *) ptr, new, _o_); \ break; \ \ case 4: \ - _r_ = ia64_cmpxchg4_##sem((__u32 *) ptr, new, _o_); \ + _r_ = ia64_cmpxchg4_##sem((__u32 __force *) ptr, new, _o_); \ break; \ \ case 8: \ - _r_ = ia64_cmpxchg8_##sem((__u64 *) ptr, new, _o_); \ + _r_ = ia64_cmpxchg8_##sem((__u64 __force *) ptr, new, _o_); \ break; \ \ default: \ _r_ = ia64_cmpxchg_called_with_bad_pointer(); \ break; \ } \ - (__typeof__(old)) _r_; \ + (__typeof__(old) __force) _r_; \ }) #define cmpxchg_acq(ptr, o, n) \ -- 2.11.0