From: Peter Zijlstra <peterz@infradead.org>
To: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
linux-kernel@vger.kernel.org, Andy Lutomirski <luto@kernel.org>,
Nadav Amit <namit@vmware.com>,
Dave Hansen <dave.hansen@intel.com>
Subject: [PATCH] x86/tlb: Revert: Align TLB invalidation info
Date: Tue, 16 Apr 2019 10:03:35 +0200 [thread overview]
Message-ID: <20190416080335.GM7905@worktop.programming.kicks-ass.net> (raw)
It was found 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.
Fixes: 515ab7c41306 ("x86/mm: Align TLB invalidation info")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
Index: linux-2.6/arch/x86/mm/tlb.c
===================================================================
--- linux-2.6.orig/arch/x86/mm/tlb.c
+++ linux-2.6/arch/x86/mm/tlb.c
@@ -728,7 +728,7 @@ 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,
.stride_shift = stride_shift,
.freed_tables = freed_tables,
next reply other threads:[~2019-04-16 8:03 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-16 8:03 Peter Zijlstra [this message]
2019-04-16 8:13 ` [tip:x86/urgent] x86/mm/tlb: Revert "x86/mm: Align TLB invalidation info" tip-bot for Peter Zijlstra
2019-04-16 17:45 ` [PATCH] x86/tlb: Revert: Align TLB invalidation info Linus Torvalds
2019-04-16 18:28 ` Peter Zijlstra
2019-04-17 4:52 ` Nadav Amit
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190416080335.GM7905@worktop.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=bp@alien8.de \
--cc=dave.hansen@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@kernel.org \
--cc=namit@vmware.com \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox