aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/process_64.c
diff options
context:
space:
mode:
authorGravatar Kirill A. Shutemov <kirill.shutemov@linux.intel.com> 2023-03-12 14:25:57 +0300
committerGravatar Dave Hansen <dave.hansen@linux.intel.com> 2023-03-16 13:08:39 -0700
commit5ef495e55f07aa117fdd8e187c9901cefc02fe0a (patch)
tree796fe02adece943b5b149acbd00f9d327a821596 /arch/x86/kernel/process_64.c
parentx86/mm: Rework address range check in get_user() and put_user() (diff)
downloadlinux-5ef495e55f07aa117fdd8e187c9901cefc02fe0a.tar.gz
linux-5ef495e55f07aa117fdd8e187c9901cefc02fe0a.tar.bz2
linux-5ef495e55f07aa117fdd8e187c9901cefc02fe0a.zip
x86: Allow atomic MM_CONTEXT flags setting
So far there's no need in atomic setting of MM context flags in mm_context_t::flags. The flags set early in exec and never change after that. LAM enabling requires atomic flag setting. The upcoming flag MM_CONTEXT_FORCE_TAGGED_SVA can be set much later in the process lifetime where multiple threads exist. Convert the field to unsigned long and do MM_CONTEXT_* accesses with __set_bit() and test_bit(). No functional changes. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Alexander Potapenko <glider@google.com> Link: https://lore.kernel.org/all/20230312112612.31869-3-kirill.shutemov%40linux.intel.com
Diffstat (limited to 'arch/x86/kernel/process_64.c')
-rw-r--r--arch/x86/kernel/process_64.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index bb65a68b4b49..cd34bcf7f860 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -671,7 +671,7 @@ void set_personality_64bit(void)
task_pt_regs(current)->orig_ax = __NR_execve;
current_thread_info()->status &= ~TS_COMPAT;
if (current->mm)
- current->mm->context.flags = MM_CONTEXT_HAS_VSYSCALL;
+ __set_bit(MM_CONTEXT_HAS_VSYSCALL, &current->mm->context.flags);
/* TBD: overwrites user setup. Should have two bits.
But 64bit processes have always behaved this way,
@@ -708,7 +708,7 @@ static void __set_personality_ia32(void)
* uprobes applied to this MM need to know this and
* cannot use user_64bit_mode() at that time.
*/
- current->mm->context.flags = MM_CONTEXT_UPROBE_IA32;
+ __set_bit(MM_CONTEXT_UPROBE_IA32, &current->mm->context.flags);
}
current->personality |= force_personality32;