Commit 06beb72f authored by Pratyush Anand's avatar Pratyush Anand Committed by Catalin Marinas
Browse files

arm64: introduce mm context flag to keep 32 bit task information 



We need to decide in some cases like uprobe instruction analysis that
whether the current mm context belongs to a 32 bit task or 64 bit.

This patch has introduced an unsigned flag variable in mm_context_t.
Currently, we set and clear TIF_32BIT depending on the condition that
whether an elf binary load sets personality for 32 bit or 64 bit
respectively.

Signed-off-by: default avatarPratyush Anand <panand@redhat.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 53d07e21

arch/arm64/include/asm/elf.h

+10 −2
Original line number Diff line number Diff line
@@ -138,7 +138,11 @@ 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)						\

({									\

	clear_bit(TIF_32BIT, &current->mm->context.flags);		\

	clear_thread_flag(TIF_32BIT);					\

})



/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */

#define ARCH_DLINFO							\
@@ -183,7 +187,11 @@ typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_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_SET_PERSONALITY(ex)					\

({									\

	set_bit(TIF_32BIT, &current->mm->context.flags);		\

	set_thread_flag(TIF_32BIT);					\

 })

#define COMPAT_ARCH_DLINFO

extern int aarch32_setup_vectors_page(struct linux_binprm *bprm,

				      int uses_interp);

arch/arm64/include/asm/mmu.h

+1 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
typedef struct {

	atomic64_t	id;

	void		*vdso;

	unsigned long	flags;

} mm_context_t;



/*

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