From 14951beaec93696b092a906baa0f29322cf34004 Mon Sep 17 00:00:00 2001 From: Wei Li Date: Tue, 23 Apr 2024 17:35:01 +0800 Subject: [PATCH 1/2] arm64: armv8_deprecated: Fix warning in isndep cpuhp starting process The function run_all_insn_set_hw_mode() is registered as startup callback of 'CPUHP_AP_ARM64_ISNDEP_STARTING', it invokes set_hw_mode() methods of all emulated instructions. As the STARTING callbacks are not expected to fail, if one of the set_hw_mode() fails, e.g. due to el0 mixed-endian is not supported for 'setend', it will report a warning: ``` CPU[2] cannot support the emulation of setend CPU 2 UP state arm64/isndep:starting (136) failed (-22) CPU2: Booted secondary processor 0x0000000002 [0x414fd0c1] ``` To fix it, add a check for INSN_UNAVAILABLE status and skip the process. Signed-off-by: Wei Li Tested-by: Huisong Li Link: https://lore.kernel.org/r/20240423093501.3460764-1-liwei391@huawei.com Signed-off-by: Will Deacon --- arch/arm64/kernel/armv8_deprecated.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c index dd6ce86d4332..b776e7424fe9 100644 --- a/arch/arm64/kernel/armv8_deprecated.c +++ b/arch/arm64/kernel/armv8_deprecated.c @@ -462,6 +462,9 @@ static int run_all_insn_set_hw_mode(unsigned int cpu) for (int i = 0; i < ARRAY_SIZE(insn_emulations); i++) { struct insn_emulation *insn = insn_emulations[i]; bool enable = READ_ONCE(insn->current_mode) == INSN_HW; + if (insn->status == INSN_UNAVAILABLE) + continue; + if (insn->set_hw_mode && insn->set_hw_mode(enable)) { pr_warn("CPU[%u] cannot support the emulation of %s", cpu, insn->name); From 5c40e428aea644c9d924e491b1bc22fa9f272bcc Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 4 Jun 2024 22:59:57 +0200 Subject: [PATCH 2/2] arm64/io: add constant-argument check In some configurations __const_iowrite32_copy() does not get inlined and gcc runs into the BUILD_BUG(): In file included from : In function '__const_memcpy_toio_aligned32', inlined from '__const_iowrite32_copy' at arch/arm64/include/asm/io.h:203:3, inlined from '__const_iowrite32_copy' at arch/arm64/include/asm/io.h:199:20: include/linux/compiler_types.h:487:45: error: call to '__compiletime_assert_538' declared with attribute error: BUILD_BUG failed 487 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^ include/linux/compiler_types.h:468:25: note: in definition of macro '__compiletime_assert' 468 | prefix ## suffix(); \ | ^~~~~~ include/linux/compiler_types.h:487:9: note: in expansion of macro '_compiletime_assert' 487 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' 39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) | ^~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:59:21: note: in expansion of macro 'BUILD_BUG_ON_MSG' 59 | #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed") | ^~~~~~~~~~~~~~~~ arch/arm64/include/asm/io.h:193:17: note: in expansion of macro 'BUILD_BUG' 193 | BUILD_BUG(); | ^~~~~~~~~ Move the check for constant arguments into the inline function to ensure it is still constant if the compiler decides against inlining it, and mark them as __always_inline to override the logic that sometimes leads to the compiler not producing the simplified output. Note that either the __always_inline annotation or the check for a constant value are sufficient here, but combining the two looks cleaner as it also avoids the macro. With clang-8 and older, the macro was still needed, but all versions of gcc and clang can reliably perform constant folding here. Fixes: ead79118dae6 ("arm64/io: Provide a WC friendly __iowriteXX_copy()") Signed-off-by: Arnd Bergmann Reviewed-by: Mark Rutland Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20240604210006.668912-1-arnd@kernel.org Signed-off-by: Will Deacon --- arch/arm64/include/asm/io.h | 36 ++++++++++++++++-------------------- 1 file changed, 16 insertions(+), 20 deletions(-) diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h index 4ff0ae3f6d66..41fd90895dfc 100644 --- a/arch/arm64/include/asm/io.h +++ b/arch/arm64/include/asm/io.h @@ -153,8 +153,9 @@ extern void __memset_io(volatile void __iomem *, int, size_t); * emit the large TLP from the CPU. */ -static inline void __const_memcpy_toio_aligned32(volatile u32 __iomem *to, - const u32 *from, size_t count) +static __always_inline void +__const_memcpy_toio_aligned32(volatile u32 __iomem *to, const u32 *from, + size_t count) { switch (count) { case 8: @@ -196,24 +197,22 @@ static inline void __const_memcpy_toio_aligned32(volatile u32 __iomem *to, void __iowrite32_copy_full(void __iomem *to, const void *from, size_t count); -static inline void __const_iowrite32_copy(void __iomem *to, const void *from, - size_t count) +static __always_inline void +__iowrite32_copy(void __iomem *to, const void *from, size_t count) { - if (count == 8 || count == 4 || count == 2 || count == 1) { + if (__builtin_constant_p(count) && + (count == 8 || count == 4 || count == 2 || count == 1)) { __const_memcpy_toio_aligned32(to, from, count); dgh(); } else { __iowrite32_copy_full(to, from, count); } } +#define __iowrite32_copy __iowrite32_copy -#define __iowrite32_copy(to, from, count) \ - (__builtin_constant_p(count) ? \ - __const_iowrite32_copy(to, from, count) : \ - __iowrite32_copy_full(to, from, count)) - -static inline void __const_memcpy_toio_aligned64(volatile u64 __iomem *to, - const u64 *from, size_t count) +static __always_inline void +__const_memcpy_toio_aligned64(volatile u64 __iomem *to, const u64 *from, + size_t count) { switch (count) { case 8: @@ -255,21 +254,18 @@ static inline void __const_memcpy_toio_aligned64(volatile u64 __iomem *to, void __iowrite64_copy_full(void __iomem *to, const void *from, size_t count); -static inline void __const_iowrite64_copy(void __iomem *to, const void *from, - size_t count) +static __always_inline void +__iowrite64_copy(void __iomem *to, const void *from, size_t count) { - if (count == 8 || count == 4 || count == 2 || count == 1) { + if (__builtin_constant_p(count) && + (count == 8 || count == 4 || count == 2 || count == 1)) { __const_memcpy_toio_aligned64(to, from, count); dgh(); } else { __iowrite64_copy_full(to, from, count); } } - -#define __iowrite64_copy(to, from, count) \ - (__builtin_constant_p(count) ? \ - __const_iowrite64_copy(to, from, count) : \ - __iowrite64_copy_full(to, from, count)) +#define __iowrite64_copy __iowrite64_copy /* * I/O memory mapping functions.