From: Nadav Amit <namit@vmware.com>
To: Andy Lutomirski <luto@kernel.org>, "x86@kernel.org" <x86@kernel.org>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"Borislav Petkov" <bp@alien8.de>, Rik van Riel <riel@redhat.com>,
Dave Hansen <dave.hansen@intel.com>,
Michal Hocko <mhocko@suse.com>,
Sasha Levin <sasha.levin@oracle.com>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v3 1/4] x86/vm86/32: Switch to flush_tlb_mm_range() in mark_screen_rdonly()
Date: Wed, 26 Apr 2017 23:56:22 +0000 [thread overview]
Message-ID: <F05A63B8-4070-4528-B8A1-DAA66EBF94D9@vmware.com> (raw)
In-Reply-To: <791a644076fc3577ba7f7b7cafd643cc089baa7d.1492844372.git.luto@kernel.org>
It may be benign, but I don’t think that flushing the TLB without
holding the ptl or the mmap_sem (for no apparent reason) is a good
practice.
On 4/22/17, 12:01 AM, "Andy Lutomirski" <luto@kernel.org> wrote:
mark_screen_rdonly() is the last remaining caller of flush_tlb().
flush_tlb_mm_range() is potentially faster and isn't obsolete.
Compile-tested only because I don't know whether software that uses
this mechanism even exists.
Cc: Rik van Riel <riel@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
arch/x86/kernel/vm86_32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c
index 23ee89ce59a9..3eda76b3c835 100644
--- a/arch/x86/kernel/vm86_32.c
+++ b/arch/x86/kernel/vm86_32.c
@@ -193,7 +193,7 @@ static void mark_screen_rdonly(struct mm_struct *mm)
pte_unmap_unlock(pte, ptl);
out:
up_write(&mm->mmap_sem);
- flush_tlb();
+ flush_tlb_mm_range(mm, 0xA0000, 0xA0000 + 32*PAGE_SIZE, 0UL);
}
--
2.9.3
next prev parent reply other threads:[~2017-04-26 23:56 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-22 7:01 [PATCH v3 0/4] x86/mm: Straightforward TLB flush fixes/cleanups Andy Lutomirski
2017-04-22 7:01 ` [PATCH v3 1/4] x86/vm86/32: Switch to flush_tlb_mm_range() in mark_screen_rdonly() Andy Lutomirski
2017-04-26 8:26 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2017-04-26 23:56 ` Nadav Amit [this message]
2017-04-27 0:02 ` [PATCH v3 1/4] " Nadav Amit
2017-04-27 16:08 ` Andy Lutomirski
2017-04-27 22:15 ` Stas Sergeev
2017-04-27 22:17 ` Stas Sergeev
2017-04-22 7:01 ` [PATCH v3 2/4] x86/mm: Remove flush_tlb() and flush_tlb_current_task() Andy Lutomirski
2017-04-26 8:27 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2017-04-22 7:01 ` [PATCH v3 3/4] x86/mm: Make flush_tlb_mm_range() more predictable Andy Lutomirski
2017-04-26 8:27 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
2017-04-22 7:01 ` [PATCH v3 4/4] x86/mm: Fix flush_tlb_page() on Xen Andy Lutomirski
2017-04-26 8:28 ` [tip:x86/mm] " tip-bot for Andy Lutomirski
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