diff mbox

[v6,11/19] arm64:ilp32: support core dump generation for ILP32

Message ID 1447795019-30176-12-git-send-email-ynorov@caviumnetworks.com (mailing list archive)
State New, archived
Headers show

Commit Message

Yury Norov Nov. 17, 2015, 9:16 p.m. UTC 
From: Andrew Pinski <apinski@cavium.com>

This patch supports core dumping on ILP32.
We need a few extra macros (COMPAT_PR_REG_SIZE and COMPAT_PRSTATUS_SIZE) due
to size differences of the register sets.

Reviewed-by: David Daney <ddaney@caviumnetworks.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>
Signed-off-by: Andrew Pinski <Andrew.Pinski@caviumnetworks.com>
---
 arch/arm64/include/asm/elf.h | 87 ++++++++++++++++++++++++++++++++++++++------
 arch/arm64/kernel/ptrace.c   | 12 +++---
 arch/arm64/kernel/vdso.c     |  8 ++++
 3 files changed, 89 insertions(+), 18 deletions(-)

Comments

Catalin Marinas Dec. 3, 2015, 4:39 p.m. UTC | #1 
On Wed, Nov 18, 2015 at 12:16:51AM +0300, Yury Norov wrote:
> diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
> index 01e032c..8f13dac 100644
> --- a/arch/arm64/include/asm/elf.h
> +++ b/arch/arm64/include/asm/elf.h
> @@ -134,7 +134,11 @@ typedef struct user_fpsimd_state elf_fpregset_t;
[...]
> @@ -179,24 +186,80 @@ typedef compat_elf_greg_t		compat_elf_gregset_t[COMPAT_A32_ELF_NGREG];
>  					 ((x)->e_flags & EF_ARM_EABI_MASK))
>  
>  #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
> +#define COMPAT_A32_SET_PERSONALITY(ex)		\
> +do {						\
> +	clear_thread_flag(TIF_32BIT_AARCH64);	\
> +	set_thread_flag(TIF_32BIT);		\
> +} while (0)
> +#define COMPAT_A32_ARCH_DLINFO		do {} while (0)
>  
>  #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
> +#define COMPAT_A32_SET_PERSONALITY(ex)	do {} while (0)
> +#define COMPAT_A32_ARCH_DLINFO		do {} while (0)
> +#endif
> +
> +/* If ILP32 is turned on, we want to define the compat_elf_greg_t to the non compat
> +   one and define PR_REG_SIZE/PRSTATUS_SIZE/SET_PR_FPVALID so we pick up the correct
> +   ones for AARCH32. Note also the definition of the macros have to be correct for
> +   LP64 as this file is included in the standard binfmt_elf.c. */
> +#ifdef CONFIG_ARM64_ILP32
> +typedef elf_greg_t			compat_elf_greg_t;
> +typedef elf_gregset_t			compat_elf_gregset_t;
> +#define PR_REG_SIZE(S)			(is_a32_compat_task() ? 72 : 272)
> +#define PRSTATUS_SIZE(S)		(is_a32_compat_task() ? 124 : (is_ilp32_compat_task() ? 352 : 392))

Can you be more specific about these numbers, what they represent, how
they are calculated? Can you not use some sizeof()?

> +#define SET_PR_FPVALID(S, V)							\
> +do {										\
> +	*(int *) (((void *) &((S)->pr_reg)) + PR_REG_SIZE((S)->pr_reg)) = (V);	\
> +} while (0)
> +#else
> +typedef compat_a32_elf_greg_t compat_elf_greg_t;
> +typedef compat_a32_elf_gregset_t compat_elf_gregset_t;
> +#endif
>  
> +#ifdef CONFIG_ARM64_ILP32
> +#define compat_ilp32_elf_check_arch(x) ((x)->e_machine == EM_AARCH64)
> +#define COMPAT_ILP32_SET_PERSONALITY(ex)	\
> +do {						\
> +	set_thread_flag(TIF_32BIT_AARCH64);	\
> +	clear_thread_flag(TIF_32BIT);		\
> +} while (0)
> +#define COMPAT_ILP32_ARCH_DLINFO					\
> +do {									\
> +	NEW_AUX_ENT(AT_SYSINFO_EHDR,					\
> +		    (elf_addr_t)(long)current->mm->context.vdso);	\
> +} while (0)
> +#else
> +#define compat_ilp32_elf_check_arch(x) 0
> +#define COMPAT_ILP32_SET_PERSONALITY(ex)	do {} while (0)
> +#define COMPAT_ILP32_ARCH_DLINFO		do {} while (0)
>  #endif
>  
> -#define compat_elf_check_arch(x)	compat_a32_elf_check_arch(x)
> +#define compat_elf_check_arch(x)	(compat_a32_elf_check_arch(x) || compat_ilp32_elf_check_arch(x))
> +#define COMPAT_SET_PERSONALITY(ex)			\
> +do {							\
> +	if (compat_a32_elf_check_arch(&ex))		\
> +		COMPAT_A32_SET_PERSONALITY(ex);		\
> +	else						\
> +		COMPAT_ILP32_SET_PERSONALITY(ex);	\
> +} while (0)
> +
> +/* ILP32 uses the "LP64-like" vdso pages */
> +#define compat_arch_setup_additional_pages	\
> +	(is_a32_compat_task()			\
> +	 ? &aarch32_setup_vectors_page		\
> +	 : &(arch_setup_additional_pages))

I thought vdso is not yet supported for ILP32. Do you still want to
insert the special mapping?

BTW, what do you do for sigreturn? It's handled by the vdso code on
AArch64.

> diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
> index 26352a6..b239b9b 100644
> --- a/arch/arm64/kernel/vdso.c
> +++ b/arch/arm64/kernel/vdso.c
> @@ -107,6 +107,14 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
>  
>  	return PTR_ERR_OR_ZERO(ret);
>  }
> +#else
> +int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
> +{
> +	(void) bprm;
> +	(void) uses_interp;

Do you get a warning for unused function arguments?

> +
> +	return -EINVAL;
> +}

A BUG() would be useful here.

Alternatively, you can define this aarch32_setup_vectors_page as NULL
when !AARCH32_EL0.
diff mbox

Patch

diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
index 01e032c..8f13dac 100644
--- a/arch/arm64/include/asm/elf.h
+++ b/arch/arm64/include/asm/elf.h
@@ -134,7 +134,11 @@  typedef struct user_fpsimd_state elf_fpregset_t;
  */
 #define ELF_PLAT_INIT(_r, load_addr)	(_r)->regs[0] = 0
 
-#define SET_PERSONALITY(ex)		clear_thread_flag(TIF_32BIT);
+#define SET_PERSONALITY(ex)			\
+do {						\
+	clear_thread_flag(TIF_32BIT_AARCH64);	\
+	clear_thread_flag(TIF_32BIT);		\
+} while (0)
 
 #define ARCH_DLINFO							\
 do {									\
@@ -166,12 +170,15 @@  extern int arch_setup_additional_pages(struct linux_binprm *bprm,
 
 #define COMPAT_ELF_ET_DYN_BASE		(2 * TASK_SIZE_32 / 3)
 
+extern int aarch32_setup_vectors_page(struct linux_binprm *bprm,
+				      int uses_interp);
+
 #ifdef CONFIG_AARCH32_EL0
 
 /* AArch32 registers. */
 #define COMPAT_A32_ELF_NGREG		18
-typedef unsigned int			compat_elf_greg_t;
-typedef compat_elf_greg_t		compat_elf_gregset_t[COMPAT_A32_ELF_NGREG];
+typedef unsigned int			compat_a32_elf_greg_t;
+typedef compat_a32_elf_greg_t		compat_a32_elf_gregset_t[COMPAT_A32_ELF_NGREG];
 
 /* AArch32 EABI. */
 #define EF_ARM_EABI_MASK		0xff000000
@@ -179,24 +186,80 @@  typedef compat_elf_greg_t		compat_elf_gregset_t[COMPAT_A32_ELF_NGREG];
 					 ((x)->e_flags & EF_ARM_EABI_MASK))
 
 #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
+#define COMPAT_A32_SET_PERSONALITY(ex)		\
+do {						\
+	clear_thread_flag(TIF_32BIT_AARCH64);	\
+	set_thread_flag(TIF_32BIT);		\
+} while (0)
+#define COMPAT_A32_ARCH_DLINFO		do {} while (0)
 
 #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
+#define COMPAT_A32_SET_PERSONALITY(ex)	do {} while (0)
+#define COMPAT_A32_ARCH_DLINFO		do {} while (0)
+#endif
+
+/* If ILP32 is turned on, we want to define the compat_elf_greg_t to the non compat
+   one and define PR_REG_SIZE/PRSTATUS_SIZE/SET_PR_FPVALID so we pick up the correct
+   ones for AARCH32. Note also the definition of the macros have to be correct for
+   LP64 as this file is included in the standard binfmt_elf.c. */
+#ifdef CONFIG_ARM64_ILP32
+typedef elf_greg_t			compat_elf_greg_t;
+typedef elf_gregset_t			compat_elf_gregset_t;
+#define PR_REG_SIZE(S)			(is_a32_compat_task() ? 72 : 272)
+#define PRSTATUS_SIZE(S)		(is_a32_compat_task() ? 124 : (is_ilp32_compat_task() ? 352 : 392))
+#define SET_PR_FPVALID(S, V)							\
+do {										\
+	*(int *) (((void *) &((S)->pr_reg)) + PR_REG_SIZE((S)->pr_reg)) = (V);	\
+} while (0)
+#else
+typedef compat_a32_elf_greg_t compat_elf_greg_t;
+typedef compat_a32_elf_gregset_t compat_elf_gregset_t;
+#endif
 
+#ifdef CONFIG_ARM64_ILP32
+#define compat_ilp32_elf_check_arch(x) ((x)->e_machine == EM_AARCH64)
+#define COMPAT_ILP32_SET_PERSONALITY(ex)	\
+do {						\
+	set_thread_flag(TIF_32BIT_AARCH64);	\
+	clear_thread_flag(TIF_32BIT);		\
+} while (0)
+#define COMPAT_ILP32_ARCH_DLINFO					\
+do {									\
+	NEW_AUX_ENT(AT_SYSINFO_EHDR,					\
+		    (elf_addr_t)(long)current->mm->context.vdso);	\
+} while (0)
+#else
+#define compat_ilp32_elf_check_arch(x) 0
+#define COMPAT_ILP32_SET_PERSONALITY(ex)	do {} while (0)
+#define COMPAT_ILP32_ARCH_DLINFO		do {} while (0)
 #endif
 
-#define compat_elf_check_arch(x)	compat_a32_elf_check_arch(x)
+#define compat_elf_check_arch(x)	(compat_a32_elf_check_arch(x) || compat_ilp32_elf_check_arch(x))
+#define COMPAT_SET_PERSONALITY(ex)			\
+do {							\
+	if (compat_a32_elf_check_arch(&ex))		\
+		COMPAT_A32_SET_PERSONALITY(ex);		\
+	else						\
+		COMPAT_ILP32_SET_PERSONALITY(ex);	\
+} while (0)
+
+/* ILP32 uses the "LP64-like" vdso pages */
+#define compat_arch_setup_additional_pages	\
+	(is_a32_compat_task()			\
+	 ? &aarch32_setup_vectors_page		\
+	 : &(arch_setup_additional_pages))
+
+#define COMPAT_ARCH_DLINFO			\
+do {						\
+	if (is_a32_compat_task())		\
+		COMPAT_A32_ARCH_DLINFO;		\
+	else					\
+		COMPAT_ILP32_ARCH_DLINFO;	\
+} while (0)
 
 #endif /* CONFIG_COMPAT */
 
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index d2e428c..22d0d5e 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -854,8 +854,8 @@  static const struct user_regset aarch32_regsets[] = {
 	[REGSET_COMPAT_GPR] = {
 		.core_note_type = NT_PRSTATUS,
 		.n = COMPAT_A32_ELF_NGREG,
-		.size = sizeof(compat_elf_greg_t),
-		.align = sizeof(compat_elf_greg_t),
+		.size = sizeof(compat_a32_elf_greg_t),
+		.align = sizeof(compat_a32_elf_greg_t),
 		.get = compat_gpr_get,
 		.set = compat_gpr_set
 	},
@@ -946,7 +946,7 @@  static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
 		tmp = tsk->mm->start_data;
 	else if (off == COMPAT_PT_TEXT_END_ADDR)
 		tmp = tsk->mm->end_code;
-	else if (off < sizeof(compat_elf_gregset_t))
+	else if (off < sizeof(compat_a32_elf_gregset_t))
 		return copy_regset_to_user(tsk, &user_aarch32_view,
 					   REGSET_COMPAT_GPR, off,
 					   sizeof(compat_ulong_t), ret);
@@ -967,7 +967,7 @@  static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
 	if (off & 3 || off >= COMPAT_USER_SZ)
 		return -EIO;
 
-	if (off >= sizeof(compat_elf_gregset_t))
+	if (off >= sizeof(compat_a32_elf_gregset_t))
 		return 0;
 
 	set_fs(KERNEL_DS);
@@ -1130,7 +1130,7 @@  long compat_a32_arch_ptrace(struct task_struct *child, compat_long_t request,
 			ret = copy_regset_to_user(child,
 						  &user_aarch32_view,
 						  REGSET_COMPAT_GPR,
-						  0, sizeof(compat_elf_gregset_t),
+						  0, sizeof(compat_a32_elf_gregset_t),
 						  datap);
 			break;
 
@@ -1138,7 +1138,7 @@  long compat_a32_arch_ptrace(struct task_struct *child, compat_long_t request,
 			ret = copy_regset_from_user(child,
 						    &user_aarch32_view,
 						    REGSET_COMPAT_GPR,
-						    0, sizeof(compat_elf_gregset_t),
+						    0, sizeof(compat_a32_elf_gregset_t),
 						    datap);
 			break;
 
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index 26352a6..b239b9b 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -107,6 +107,14 @@  int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
 
 	return PTR_ERR_OR_ZERO(ret);
 }
+#else
+int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
+{
+	(void) bprm;
+	(void) uses_interp;
+
+	return -EINVAL;
+}
 #endif /* CONFIG_AARCH32_EL0 */
 
 static struct vm_special_mapping vdso_spec[2];