diff options
| author | Gabriel Krisman Bertazi <krisman@collabora.com> | 2020-10-04 06:25:35 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-10-26 15:46:47 +0300 |
| commit | ff170cd0595398a7b66cb40f249eb2f10c29b66d (patch) | |
| tree | aaea8a15b4b7675f326d2cf8936e67fce26fd5f3 /arch/x86/include/asm/mmu_context.h | |
| parent | 3316ec8ccd34e19690a12e65801d605d25155031 (diff) | |
| download | linux-ff170cd0595398a7b66cb40f249eb2f10c29b66d.tar.xz | |
x86/mm: Convert mmu context ia32_compat into a proper flags field
The ia32_compat attribute is a weird thing. It mirrors TIF_IA32 and
TIF_X32 and is used only in two very unrelated places: (1) to decide if
the vsyscall page is accessible (2) for uprobes to find whether the
patched instruction is 32 or 64 bit.
In preparation to remove the TIF flags, a new mechanism is required for
ia32_compat, but given its odd semantics, adding a real flags field which
configures these specific behaviours is the best option.
So, set_personality_x64() can ask for the vsyscall page, which is not
available in x32/ia32 and set_personality_ia32() can configure the uprobe
code as needed.
uprobe cannot rely on other methods like user_64bit_mode() to decide how
to patch, so it needs some specific flag like this.
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski<luto@kernel.org>
Link: https://lore.kernel.org/r/20201004032536.1229030-10-krisman@collabora.com
Diffstat (limited to 'arch/x86/include/asm/mmu_context.h')
| -rw-r--r-- | arch/x86/include/asm/mmu_context.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index d98016b83755..054a79157323 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -177,7 +177,7 @@ static inline void arch_exit_mmap(struct mm_struct *mm) static inline bool is_64bit_mm(struct mm_struct *mm) { return !IS_ENABLED(CONFIG_IA32_EMULATION) || - !(mm->context.ia32_compat == TIF_IA32); + !(mm->context.flags & MM_CONTEXT_UPROBE_IA32); } #else static inline bool is_64bit_mm(struct mm_struct *mm) |