From b7c35279e0da414e7d90eba76f58a16223a734cb Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Tue, 2 Jul 2024 13:21:39 +0000 Subject: [PATCH] x86/mm: Cleanup prctl_enable_tagged_addr() nr_bits error checking There are two separate checks in prctl_enable_tagged_addr() that nr_bits is in the correct range. The checks are arranged such the correct case is sandwiched between both error cases, which do exactly the same thing. Simplify the if condition and pull the correct case outside with the rest of the success code path. Signed-off-by: Yosry Ahmed Signed-off-by: Dave Hansen Reviewed-by: Kirill A. Shutemov Link: https://lore.kernel.org/all/20240702132139.3332013-4-yosryahmed%40google.com --- arch/x86/kernel/process_64.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index e9f7cfdb94202..226472332a70d 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -812,6 +812,9 @@ static void enable_lam_func(void *__mm) static void mm_enable_lam(struct mm_struct *mm) { + mm->context.lam_cr3_mask = X86_CR3_LAM_U57; + mm->context.untag_mask = ~GENMASK(62, 57); + /* * Even though the process must still be single-threaded at this * point, kernel threads may be using the mm. IPI those kernel @@ -846,13 +849,7 @@ static int prctl_enable_tagged_addr(struct mm_struct *mm, unsigned long nr_bits) return -EBUSY; } - if (!nr_bits) { - mmap_write_unlock(mm); - return -EINVAL; - } else if (nr_bits <= LAM_U57_BITS) { - mm->context.lam_cr3_mask = X86_CR3_LAM_U57; - mm->context.untag_mask = ~GENMASK(62, 57); - } else { + if (!nr_bits || nr_bits > LAM_U57_BITS) { mmap_write_unlock(mm); return -EINVAL; }