| Message ID | 20240108174330.472996-2-leobras@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,1/1] arm64: remove unnecessary ifdefs around is_compat_task() | expand |
On Mon, Jan 8, 2024, at 18:43, Leonardo Bras wrote: > Currently some parts of the codebase will test for CONFIG_COMPAT before > testing is_compat_task(). > > is_compat_task() is a inlined function only present on CONFIG_COMPAT. > On the other hand, for !CONFIG_COMPAT, we have in linux/compat.h: > > #define is_compat_task() (0) > > Since we have this define available in every usage of is_compat_task() for > !CONFIG_COMPAT, it's unnecessary to keep the ifdefs, since the compiler is > smart enough to optimize-out those snippets on CONFIG_COMPAT=n > > This requires some regset code as well as a few other defines to be made > available on !CONFIG_COMPAT, so some symbols can get resolved before > getting optimized-out. > > Signed-off-by: Leonardo Bras <leobras@redhat.com> > --- > Changes since v1: > - Move some regset code and other defines outside of CONFIG_COMPAT > - Closes: > https://lore.kernel.org/oe-kbuild-all/202401061219.Y2LD7LTx-lkp@intel.com/ > Link: > https://lore.kernel.org/all/20240105041458.126602-3-leobras@redhat.com/ Looks good to me, and did not cause any regressions in an overnight randconfig build loop. Reviewed-by: Arnd Bergmann <arnd@arndb.de>
On Tue, Jan 09, 2024 at 07:18:46AM +0100, Arnd Bergmann wrote: > On Mon, Jan 8, 2024, at 18:43, Leonardo Bras wrote: > > Currently some parts of the codebase will test for CONFIG_COMPAT before > > testing is_compat_task(). > > > > is_compat_task() is a inlined function only present on CONFIG_COMPAT. > > On the other hand, for !CONFIG_COMPAT, we have in linux/compat.h: > > > > #define is_compat_task() (0) > > > > Since we have this define available in every usage of is_compat_task() for > > !CONFIG_COMPAT, it's unnecessary to keep the ifdefs, since the compiler is > > smart enough to optimize-out those snippets on CONFIG_COMPAT=n > > > > This requires some regset code as well as a few other defines to be made > > available on !CONFIG_COMPAT, so some symbols can get resolved before > > getting optimized-out. > > > > Signed-off-by: Leonardo Bras <leobras@redhat.com> > > --- > > Changes since v1: > > - Move some regset code and other defines outside of CONFIG_COMPAT > > - Closes: > > https://lore.kernel.org/oe-kbuild-all/202401061219.Y2LD7LTx-lkp@intel.com/ > > Link: > > https://lore.kernel.org/all/20240105041458.126602-3-leobras@redhat.com/ > > Looks good to me, and did not cause any regressions in an overnight > randconfig build loop. > > Reviewed-by: Arnd Bergmann <arnd@arndb.de> > Thanks! Leo
diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h index 97932fbf973d1..3f93f4eef9530 100644 --- a/arch/arm64/include/asm/elf.h +++ b/arch/arm64/include/asm/elf.h @@ -201,16 +201,16 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm, #define COMPAT_ELF_PLATFORM ("v8l") #endif -#ifdef CONFIG_COMPAT - -/* PIE load location for compat arm. Must match ARM ELF_ET_DYN_BASE. */ -#define COMPAT_ELF_ET_DYN_BASE 0x000400000UL - /* AArch32 registers. */ #define COMPAT_ELF_NGREG 18 typedef unsigned int compat_elf_greg_t; typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG]; +#ifdef CONFIG_COMPAT + +/* PIE load location for compat arm. Must match ARM ELF_ET_DYN_BASE. */ +#define COMPAT_ELF_ET_DYN_BASE 0x000400000UL + /* AArch32 EABI. */ #define EF_ARM_EABI_MASK 0xff000000 int compat_elf_check_arch(const struct elf32_hdr *); diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index 50e5f25d3024c..94c7ed82fbada 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -21,7 +21,6 @@ #include <linux/stddef.h> #include <linux/types.h> -#ifdef CONFIG_COMPAT /* Masks for extracting the FPSR and FPCR from the FPSCR */ #define VFP_FPSCR_STAT_MASK 0xf800009f #define VFP_FPSCR_CTRL_MASK 0x07f79f00 @@ -30,7 +29,6 @@ * control/status register. */ #define VFP_STATE_SIZE ((32 * 8) + 4) -#endif static inline unsigned long cpacr_save_enable_kernel_sve(void) { diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 20d7ef82de90a..27efd66fc1e93 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -173,7 +173,6 @@ static void ptrace_hbptriggered(struct perf_event *bp, struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp); const char *desc = "Hardware breakpoint trap (ptrace)"; -#ifdef CONFIG_COMPAT if (is_compat_task()) { int si_errno = 0; int i; @@ -195,7 +194,7 @@ static void ptrace_hbptriggered(struct perf_event *bp, desc); return; } -#endif + arm64_force_sig_fault(SIGTRAP, TRAP_HWBKPT, bkpt->trigger, desc); } @@ -1594,7 +1593,6 @@ static const struct user_regset_view user_aarch64_view = { .regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets) }; -#ifdef CONFIG_COMPAT enum compat_regset { REGSET_COMPAT_GPR, REGSET_COMPAT_VFP, @@ -1851,6 +1849,7 @@ static const struct user_regset_view user_aarch32_ptrace_view = { .regsets = aarch32_ptrace_regsets, .n = ARRAY_SIZE(aarch32_ptrace_regsets) }; +#ifdef CONFIG_COMPAT static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off, compat_ulong_t __user *ret) { @@ -2112,7 +2111,6 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, const struct user_regset_view *task_user_regset_view(struct task_struct *task) { -#ifdef CONFIG_COMPAT /* * Core dumping of 32-bit tasks or compat ptrace requests must use the * user_aarch32_view compatible with arm32. Native ptrace requests on @@ -2123,7 +2121,7 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) return &user_aarch32_view; else if (is_compat_thread(task_thread_info(task))) return &user_aarch32_ptrace_view; -#endif + return &user_aarch64_view; } diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c index 9a70d9746b661..ad198262b9817 100644 --- a/arch/arm64/kernel/syscall.c +++ b/arch/arm64/kernel/syscall.c @@ -20,14 +20,11 @@ long sys_ni_syscall(void); static long do_ni_syscall(struct pt_regs *regs, int scno) { -#ifdef CONFIG_COMPAT - long ret; if (is_compat_task()) { - ret = compat_arm_syscall(regs, scno); + long ret = compat_arm_syscall(regs, scno); if (ret != -ENOSYS) return ret; } -#endif return sys_ni_syscall(); }
Currently some parts of the codebase will test for CONFIG_COMPAT before testing is_compat_task(). is_compat_task() is a inlined function only present on CONFIG_COMPAT. On the other hand, for !CONFIG_COMPAT, we have in linux/compat.h: #define is_compat_task() (0) Since we have this define available in every usage of is_compat_task() for !CONFIG_COMPAT, it's unnecessary to keep the ifdefs, since the compiler is smart enough to optimize-out those snippets on CONFIG_COMPAT=n This requires some regset code as well as a few other defines to be made available on !CONFIG_COMPAT, so some symbols can get resolved before getting optimized-out. Signed-off-by: Leonardo Bras <leobras@redhat.com> --- Changes since v1: - Move some regset code and other defines outside of CONFIG_COMPAT - Closes: https://lore.kernel.org/oe-kbuild-all/202401061219.Y2LD7LTx-lkp@intel.com/ Link: https://lore.kernel.org/all/20240105041458.126602-3-leobras@redhat.com/ Changes since RFCv1: - Removed unnecessary new inlined is_compat_task() for arm64 - Adjusted commit text and title Link: https://lore.kernel.org/all/20240104192433.109983-2-leobras@redhat.com/ arch/arm64/include/asm/elf.h | 10 +++++----- arch/arm64/include/asm/fpsimd.h | 2 -- arch/arm64/kernel/ptrace.c | 8 +++----- arch/arm64/kernel/syscall.c | 5 +---- 4 files changed, 9 insertions(+), 16 deletions(-)