| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.19 97/99] x86/mm/tlb: Revert "x86/mm: Align TLB invalidation info" | Date | Mon, 6 May 2019 16:33:10 +0200 |
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From: Peter Zijlstra <peterz@infradead.org>
commit 780e0106d468a2962b16b52fdf42898f2639e0a0 upstream.
Revert the following commit:
515ab7c41306: ("x86/mm: Align TLB invalidation info")
I found out (the hard way) that under some .config options (notably L1_CACHE_SHIFT=7) and compiler combinations this on-stack alignment leads to a 320 byte stack usage, which then triggers a KASAN stack warning elsewhere.
Using 320 bytes of stack space for a 40 byte structure is ludicrous and clearly not right.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Nadav Amit <namit@vmware.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 515ab7c41306 ("x86/mm: Align TLB invalidation info") Link: http://lkml.kernel.org/r/20190416080335.GM7905@worktop.programming.kicks-ass.net [ Minor changelog edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- arch/x86/mm/tlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -694,7 +694,7 @@ void flush_tlb_mm_range(struct mm_struct { int cpu; - struct flush_tlb_info info __aligned(SMP_CACHE_BYTES) = { + struct flush_tlb_info info = { .mm = mm, };
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