From: Andrey Konovalov <andrey.konovalov@linaro.org>
To: Yury Norov <ynorov@caviumnetworks.com>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, catalin.marinas@arm.com,
arnd@arndb.de, agraf@suse.de, bamvor.zhangjian@huawei.com
Cc: yury.norov@gmail.com, klimov.linux@gmail.com, apinski@cavium.com,
philipp.tomsich@theobroma-systems.com,
christoph.muellner@theobroma-systems.com
Subject: Re: [PATCH v5 04/23] arm64: change some CONFIG_COMPAT over to use CONFIG_AARCH32_EL0 instead
Date: Tue, 6 Oct 2015 12:21:20 +0300 [thread overview]
Message-ID: <56139290.8090300@linaro.org> (raw)
In-Reply-To: <1443564860-31208-5-git-send-email-ynorov@caviumnetworks.com>
Hi Yury,
With this patch set 4.3 kernel fails to build with both arch/arm64/configs/defconfig,
and with arch/arm64/configs/defconfig plus CONFIG_AARCH32_EL0=y and CONFIG_ARM64_ILP32=y.
See the details below.
Thanks,
Andrey
On 09/30/2015 01:14 AM, Yury Norov wrote:
> From: Andrew Pinski <apinski@cavium.com>
>
> Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
> Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
> Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
>
> diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
> index faad6df..f40c51b 100644
> --- a/arch/arm64/include/asm/elf.h
> +++ b/arch/arm64/include/asm/elf.h
> @@ -166,10 +166,13 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,
>
> #define COMPAT_ELF_ET_DYN_BASE (2 * TASK_SIZE_32 / 3)
>
> +
> +#ifdef CONFIG_AARCH32_EL0
> +
> /* AArch32 registers. */
> -#define COMPAT_ELF_NGREG 18
> +#define COMPAT_A32_ELF_NGREG 18
> typedef unsigned int compat_elf_greg_t;
> -typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG];
> +typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_A32_ELF_NGREG];
>
> /* AArch32 EABI. */
> #define EF_ARM_EABI_MASK 0xff000000
> @@ -179,11 +182,25 @@ typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG];
> #define compat_start_thread compat_start_thread
> #define COMPAT_SET_PERSONALITY(ex) set_thread_flag(TIF_32BIT);
> #define COMPAT_ARCH_DLINFO
> +
> +
> extern int aarch32_setup_vectors_page(struct linux_binprm *bprm,
> int uses_interp);
> #define compat_arch_setup_additional_pages \
> aarch32_setup_vectors_page
>
> +#else
> +
> +typedef elf_greg_t compat_elf_greg_t;
> +typedef elf_gregset_t compat_elf_gregset_t;
> +#define compat_a32_elf_check_arch(x) 0
> +#define COMPAT_SET_PERSONALITY(ex)
> +#define COMPAT_ARCH_DLINFO
> +
> +#endif
> +
> +#define compat_elf_check_arch(x) compat_a32_elf_check_arch(x)
> +
> #endif /* CONFIG_COMPAT */
>
> #endif
> diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h
> index 50f559f..63b19f1 100644
> --- a/arch/arm64/include/asm/fpsimd.h
> +++ b/arch/arm64/include/asm/fpsimd.h
> @@ -52,7 +52,7 @@ struct fpsimd_partial_state {
> };
>
>
> -#if defined(__KERNEL__) && defined(CONFIG_COMPAT)
> +#if defined(__KERNEL__) && defined(CONFIG_AARCH32_EL0)
> /* Masks for extracting the FPSR and FPCR from the FPSCR */
> #define VFP_FPSCR_STAT_MASK 0xf800009f
> #define VFP_FPSCR_CTRL_MASK 0x07f79f00
> diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
> index 536274e..1059b3f 100644
> --- a/arch/arm64/include/asm/ptrace.h
> +++ b/arch/arm64/include/asm/ptrace.h
> @@ -120,7 +120,7 @@ struct pt_regs {
>
> #define arch_has_single_step() (1)
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> #define compat_thumb_mode(regs) \
> (((regs)->pstate & COMPAT_PSR_T_BIT))
> #else
> diff --git a/arch/arm64/include/asm/signal32.h b/arch/arm64/include/asm/signal32.h
> index eeaa975..4302909 100644
> --- a/arch/arm64/include/asm/signal32.h
> +++ b/arch/arm64/include/asm/signal32.h
> @@ -20,6 +20,7 @@
> #ifdef CONFIG_COMPAT
> #include <linux/compat.h>
>
> +#ifdef CONFIG_AARCH32_EL0
> #define AARCH32_KERN_SIGRET_CODE_OFFSET 0x500
>
> extern const compat_ulong_t aarch32_sigret_code[6];
> @@ -47,6 +48,7 @@ static inline int compat_setup_rt_frame(int usig, struct ksignal *ksig, sigset_t
> static inline void compat_setup_restart_syscall(struct pt_regs *regs)
> {
> }
> +#endif /* CONFIG_AARCH32_EL0 */
> #endif /* CONFIG_COMPAT */
> #endif /* __KERNEL__ */
> #endif /* __ASM_SIGNAL32_H */
> diff --git a/arch/arm64/include/asm/stat.h b/arch/arm64/include/asm/stat.h
> index 15e3559..af04276 100644
> --- a/arch/arm64/include/asm/stat.h
> +++ b/arch/arm64/include/asm/stat.h
> @@ -22,6 +22,7 @@
>
> #include <asm/compat.h>
>
> +#ifdef CONFIG_AARCH32_EL0
> /*
> * struct stat64 is needed for compat tasks only. Its definition is different
> * from the generic struct stat64.
> @@ -59,3 +60,4 @@ struct stat64 {
>
> #endif
> #endif
> +#endif
> diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
> index 3bc498c..759c433 100644
> --- a/arch/arm64/include/asm/unistd.h
> +++ b/arch/arm64/include/asm/unistd.h
> @@ -13,7 +13,7 @@
> * You should have received a copy of the GNU General Public License
> * along with this program. If not, see <http://www.gnu.org/licenses/>.
> */
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> #define __ARCH_WANT_COMPAT_SYS_GETDENTS64
> #define __ARCH_WANT_COMPAT_STAT64
> #define __ARCH_WANT_SYS_GETHOSTNAME
> @@ -26,7 +26,9 @@
> #define __ARCH_WANT_COMPAT_SYS_SENDFILE
> #define __ARCH_WANT_SYS_FORK
> #define __ARCH_WANT_SYS_VFORK
> +#endif
>
> +#ifdef CONFIG_COMPAT
> /*
> * Compat syscall numbers used by the AArch64 kernel.
> */
> diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
> index 22dc9bc..1470332 100644
> --- a/arch/arm64/kernel/Makefile
> +++ b/arch/arm64/kernel/Makefile
> @@ -20,7 +20,7 @@ arm64-obj-y := debug-monitors.o entry.o irq.o fpsimd.o \
> cpufeature.o alternative.o cacheinfo.o \
> smp.o smp_spin_table.o topology.o
>
> -arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \
> +arm64-obj-$(CONFIG_AARCH32_EL0) += sys32.o kuser32.o signal32.o \
> sys_compat.o entry32.o \
> ../../arm/kernel/opcodes.o
> arm64-obj-$(CONFIG_FUNCTION_TRACER) += ftrace.o entry-ftrace.o
> diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
> index 8d89cf8..e3bcf77 100644
> --- a/arch/arm64/kernel/asm-offsets.c
> +++ b/arch/arm64/kernel/asm-offsets.c
> @@ -51,7 +51,7 @@ int main(void)
> DEFINE(S_X7, offsetof(struct pt_regs, regs[7]));
> DEFINE(S_LR, offsetof(struct pt_regs, regs[30]));
> DEFINE(S_SP, offsetof(struct pt_regs, sp));
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> DEFINE(S_COMPAT_SP, offsetof(struct pt_regs, compat_sp));
> #endif
> DEFINE(S_PSTATE, offsetof(struct pt_regs, pstate));
> diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
> index 4306c93..52be5c8 100644
> --- a/arch/arm64/kernel/entry.S
> +++ b/arch/arm64/kernel/entry.S
> @@ -212,7 +212,7 @@ ENTRY(vectors)
> ventry el0_fiq_invalid // FIQ 64-bit EL0
> ventry el0_error_invalid // Error 64-bit EL0
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> ventry el0_sync_compat // Synchronous 32-bit EL0
> ventry el0_irq_compat // IRQ 32-bit EL0
> ventry el0_fiq_invalid_compat // FIQ 32-bit EL0
> @@ -252,7 +252,7 @@ el0_error_invalid:
> inv_entry 0, BAD_ERROR
> ENDPROC(el0_error_invalid)
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> el0_fiq_invalid_compat:
> inv_entry 0, BAD_FIQ, 32
> ENDPROC(el0_fiq_invalid_compat)
> @@ -414,7 +414,7 @@ el0_sync:
> b.ge el0_dbg
> b el0_inv
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> .align 6
> el0_sync_compat:
> kernel_entry 0, 32
> diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
> index 90d09ed..d11d0b2 100644
> --- a/arch/arm64/kernel/head.S
> +++ b/arch/arm64/kernel/head.S
> @@ -519,7 +519,7 @@ CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems
> mov x0, #0x33ff
> msr cptr_el2, x0 // Disable copro. traps to EL2
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> msr hstr_el2, xzr // Disable CP15 traps to EL2
> #endif
>
> diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
> index 1971f49..04b4972 100644
> --- a/arch/arm64/kernel/ptrace.c
> +++ b/arch/arm64/kernel/ptrace.c
> @@ -76,7 +76,7 @@ static void ptrace_hbptriggered(struct perf_event *bp,
> .si_addr = (void __user *)(bkpt->trigger),
> };
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> int i;
>
> if (!is_compat_task())
> @@ -651,7 +651,7 @@ static const struct user_regset_view user_aarch64_view = {
> .regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
> };
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> #include <linux/compat.h>
>
> enum compat_regset {
> @@ -853,7 +853,7 @@ static int compat_tls_set(struct task_struct *target,
> static const struct user_regset aarch32_regsets[] = {
> [REGSET_COMPAT_GPR] = {
> .core_note_type = NT_PRSTATUS,
> - .n = COMPAT_ELF_NGREG,
> + .n = COMPAT_A32_ELF_NGREG,
Commit 5d220ff9 "arm64: Better native ptrace support for compat tasks" added
struct user_regset aarch32_ptrace_regsets[]
and hence one more COMPAT_ELF_NGREG, which is not handled by this patch.
This resulted in the following build failure in my ILP32 configuration (arch/arm64/configs/defconfig
plus CONFIG_AARCH32_EL0=y and CONFIG_ARM64_ILP32=y):
-----8<-----
../arch/arm64/kernel/ptrace.c:880:8: error: 'COMPAT_ELF_NGREG' undeclared here (not in a function)
.n = COMPAT_ELF_NGREG,
^
-----8<-----
> .size = sizeof(compat_elf_greg_t),
> .align = sizeof(compat_elf_greg_t),
> .get = compat_gpr_get,
> @@ -1109,8 +1109,8 @@ static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
> }
> #endif /* CONFIG_HAVE_HW_BREAKPOINT */
>
> -long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
> - compat_ulong_t caddr, compat_ulong_t cdata)
> +long compat_a32_arch_ptrace(struct task_struct *child, compat_long_t request,
> + compat_ulong_t caddr, compat_ulong_t cdata)
> {
> unsigned long addr = caddr;
> unsigned long data = cdata;
> @@ -1186,11 +1186,28 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
>
> return ret;
> }
> -#endif /* CONFIG_COMPAT */
> +#else /* !CONFIG_AARCH32_EL0 */
> +long compat_a32_arch_ptrace(struct task_struct *child, compat_long_t request,
> + compat_ulong_t caddr, compat_ulong_t cdata)
> +{
> + return -1;
> +}
> +#endif /* !CONFIG_AARCH32_EL0 */
Building with arm64's defconfig (CONFIG_AARCH32_EL0, CONFIG_COMPAT, and CONFIG_ARM64_ILP32 aren't set)
fails this way - due to compat_[u]long_t not being defined in !CONFIG_COMPAT case:
-----8<-----
../arch/arm64/kernel/ptrace.c:1190:56: error: unknown type name 'compat_long_t'
long compat_a32_arch_ptrace(struct task_struct *child, compat_long_t request,
^
../arch/arm64/kernel/ptrace.c:1191:8: error: unknown type name 'compat_ulong_t'
compat_ulong_t caddr, compat_ulong_t cdata)
^
../arch/arm64/kernel/ptrace.c:1191:30: error: unknown type name 'compat_ulong_t'
compat_ulong_t caddr, compat_ulong_t cdata)
^
-----8<-----
> +#ifdef CONFIG_COMPAT
> +long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
> + compat_ulong_t caddr, compat_ulong_t cdata)
> +{
> + if (is_compat_task())
> + return compat_a32_arch_ptrace(child, request, caddr, cdata);
> + return compat_ptrace_request(child, request, caddr, cdata);
> +}
> +#endif
> +
>
> const struct user_regset_view *task_user_regset_view(struct task_struct *task)
> {
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> /*
> * Core dumping of 32-bit tasks or compat ptrace requests must use the
> * user_aarch32_view compatible with arm32. Native ptrace requests on
> diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
> index e18c48c..964a2a4 100644
> --- a/arch/arm64/kernel/signal.c
> +++ b/arch/arm64/kernel/signal.c
> @@ -414,3 +414,18 @@ asmlinkage void do_notify_resume(struct pt_regs *regs,
> fpsimd_restore_current_state();
>
> }
> +
> +/*
> + * Some functions are needed for compat ptrace but we don't define
> + * them if we don't have AARCH32 support compiled in
> + */
> +#if defined CONFIG_COMPAT && !defined CONFIG_AARCH32_EL0
> +int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from)
> +{
> + return -EFAULT;
> +}
> +int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
> +{
> + return -EFAULT;
> +}
> +#endif
> diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
> index f93aae5..9ce9894 100644
> --- a/arch/arm64/kernel/traps.c
> +++ b/arch/arm64/kernel/traps.c
> @@ -363,7 +363,7 @@ long compat_arm_syscall(struct pt_regs *regs);
>
> asmlinkage long do_ni_syscall(struct pt_regs *regs)
> {
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> long ret;
> if (is_compat_task()) {
> ret = compat_arm_syscall(regs);
> diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
> index 97bc68f..26352a6 100644
> --- a/arch/arm64/kernel/vdso.c
> +++ b/arch/arm64/kernel/vdso.c
> @@ -49,7 +49,7 @@ static union {
> } vdso_data_store __page_aligned_data;
> struct vdso_data *vdso_data = &vdso_data_store.data;
>
> -#ifdef CONFIG_COMPAT
> +#ifdef CONFIG_AARCH32_EL0
> /*
> * Create and map the vectors page for AArch32 tasks.
> */
> @@ -107,7 +107,7 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
>
> return PTR_ERR_OR_ZERO(ret);
> }
> -#endif /* CONFIG_COMPAT */
> +#endif /* CONFIG_AARCH32_EL0 */
>
> static struct vm_special_mapping vdso_spec[2];
>
>
next prev parent reply other threads:[~2015-10-06 9:21 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-29 22:13 [PATCH v5 00/23] ILP32 for ARM64 Yury Norov
2015-09-29 22:13 ` [PATCH v5 01/23] arm64:ilp32: add documentation on the ILP32 ABI " Yury Norov
2015-09-29 22:13 ` [PATCH v5 02/23] arm64: ensure the kernel is compiled for LP64 Yury Norov
2015-09-29 22:14 ` [PATCH v5 03/23] arm64: rename COMPAT to AARCH32_EL0 in Kconfig Yury Norov
2015-10-06 9:21 ` Andrey Konovalov
2015-09-29 22:14 ` [PATCH v5 04/23] arm64: change some CONFIG_COMPAT over to use CONFIG_AARCH32_EL0 instead Yury Norov
2015-09-30 3:36 ` kbuild test robot
2015-09-30 5:35 ` kbuild test robot
2015-10-06 9:21 ` Andrey Konovalov [this message]
2015-09-29 22:14 ` [PATCH v5 05/23] arm64:ilp32: expose 'kernel_long' as 'long long' for ILP32 Yury Norov
2015-09-29 22:14 ` [PATCH v5 06/23] arm64:uapi: set __BITS_PER_LONG correctly for ILP32 and LP64 Yury Norov
2015-09-29 22:14 ` [PATCH v5 07/23] arm64:ilp32: share signal structures between ILP32 and LP64 ABIs Yury Norov
2015-09-29 22:14 ` [PATCH v5 08/23] arm64:ilp32: use 64bit syscall-names for ILP32 when passing 64bit registers Yury Norov
2015-09-29 22:14 ` [PATCH v5 09/23] arm64:ilp32: use non-compat syscall names for ILP32 as for LP64 Yury Norov
2015-09-29 22:14 ` [PATCH v5 10/23] arm64: introduce is_a32_task and is_a32_thread (for AArch32 compat) Yury Norov
2015-09-30 3:48 ` kbuild test robot
2015-10-06 9:21 ` Andrey Konovalov
2015-10-07 16:13 ` Yury Norov
2015-09-29 22:14 ` [PATCH v5 11/23] arm64:ilp32: add is_ilp32_compat_{task,thread} and TIF_32BIT_AARCH64 Yury Norov
2015-09-29 22:14 ` [PATCH v5 12/23] arm64:ilp32: COMPAT_USE_64BIT_TIME is true for ILP32 tasks Yury Norov
2015-09-29 22:14 ` [PATCH v5 13/23] arm64:ilp32: share HWCAP between LP64 and ILP32 Yury Norov
2015-09-29 22:14 ` [PATCH v5 14/23] arm64:ilp32 use the native LP64 'start_thread' for ILP32 threads Yury Norov
2015-09-29 22:14 ` [PATCH v5 15/23] arm64:ilp32: support core dump generation for ILP32 Yury Norov
2015-09-29 22:14 ` [PATCH v5 16/23] arm64: add support for starting ILP32 (ELFCLASS32) binaries Yury Norov
2015-09-29 22:14 ` [PATCH v5 17/23] arm64:ilp32: add vdso-ilp32 and use for signal return Yury Norov
2015-09-30 4:06 ` Nathan Lynch
2015-10-01 19:44 ` Yury Norov
2015-10-01 19:54 ` Dr. Philipp Tomsich
2015-09-29 22:14 ` [PATCH v5 18/23] ptrace: Allow compat to use the native siginfo Yury Norov
2015-09-29 22:14 ` [PATCH v5 19/23] arm64:ilp32: add sys_ilp32.c and a separate table (in entry.S) to use it Yury Norov
2015-09-29 22:14 ` [PATCH v5 20/23] arm64:ilp32: use the native siginfo instead of the compat siginfo Yury Norov
2015-09-29 22:14 ` [PATCH v5 21/23] arm64:ilp32: change COMPAT_ELF_PLATFORM to report a a subplatform for ILP32 Yury Norov
2015-09-29 22:14 ` [PATCH v5 22/23] aarch64: ilp32: msgrcv, msgsnd handlers Yury Norov
2015-09-29 22:14 ` [PATCH v5 23/23] arm64:ilp32: add ARM64_ILP32 to Kconfig Yury Norov
2015-09-30 10:19 ` [PATCH v5 00/23] ILP32 for ARM64 Catalin Marinas
2015-09-30 16:41 ` Mark Brown
2015-10-01 11:19 ` Catalin Marinas
2015-10-01 11:36 ` Mark Brown
2015-10-01 16:42 ` Andrey Konovalov
2015-10-01 19:33 ` Yury Norov
2015-10-01 19:15 ` Yury Norov
2015-10-01 21:28 ` Arnd Bergmann
2015-10-01 21:49 ` Pinski, Andrew
2015-10-02 9:37 ` Catalin Marinas
2015-10-03 2:18 ` Kapoor, Prasun
2015-10-05 15:58 ` Catalin Marinas
2015-10-05 21:00 ` Pinski, Andrew
2015-10-05 19:10 ` Yury Norov
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