From: Thomas Gleixner <tglx@linutronix.de>
To: Vlastimil Babka <vbabka@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>,
Josh Poimboeuf <jpoimboe@redhat.com>,
LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
Sean Christopherson <sean.j.christopherson@intel.com>,
Andrew Morton <akpm@linux-foundation.org>,
Pekka Enberg <penberg@kernel.org>, Linux-MM <linux-mm@kvack.org>,
David Rientjes <rientjes@google.com>
Subject: [patch V5 01/32] mm/slab: Remove broken stack trace storage
Date: Tue, 16 Apr 2019 16:10:25 +0200 (CEST) [thread overview]
Message-ID: <alpine.DEB.2.21.1904161608570.1685@nanos.tec.linutronix.de> (raw)
In-Reply-To: <612f9b99-a75b-6aeb-cf92-7dc5421cd950@suse.cz>
kstack_end() is broken on interrupt stacks as they are not guaranteed to be
sized THREAD_SIZE and THREAD_SIZE aligned.
As SLAB seems not to be used much with debugging enabled and might just go
away completely according to:
https://lkml.kernel.org/r/612f9b99-a75b-6aeb-cf92-7dc5421cd950@suse.cz
just remove the bogus code instead of trying to fix it.
Fixes: 98eb235b7feb ("[PATCH] page unmapping debug") - History tree
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: linux-mm@kvack.org
---
V5: Remove the cruft.
V4: Make it actually work
V2: Made the code simpler to understand (Andy)
---
mm/slab.c | 22 +++-------------------
1 file changed, 3 insertions(+), 19 deletions(-)
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1470,33 +1470,17 @@ static bool is_debug_pagealloc_cache(str
static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr,
unsigned long caller)
{
- int size = cachep->object_size;
+ int size = cachep->object_size / sizeof(unsigned long);
addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)];
- if (size < 5 * sizeof(unsigned long))
+ if (size < 4)
return;
*addr++ = 0x12345678;
*addr++ = caller;
*addr++ = smp_processor_id();
- size -= 3 * sizeof(unsigned long);
- {
- unsigned long *sptr = &caller;
- unsigned long svalue;
-
- while (!kstack_end(sptr)) {
- svalue = *sptr++;
- if (kernel_text_address(svalue)) {
- *addr++ = svalue;
- size -= sizeof(unsigned long);
- if (size <= sizeof(unsigned long))
- break;
- }
- }
-
- }
- *addr++ = 0x87654321;
+ *addr = 0x87654321;
}
static void slab_kernel_map(struct kmem_cache *cachep, void *objp,
next prev parent reply other threads:[~2019-04-16 14:10 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20190414155936.679808307@linutronix.de>
2019-04-14 15:59 ` [patch V3 01/32] mm/slab: Fix broken stack trace storage Thomas Gleixner
2019-04-14 16:16 ` Andy Lutomirski
2019-04-14 16:34 ` Thomas Gleixner
2019-04-15 9:02 ` [patch V4 " Thomas Gleixner
2019-04-15 13:23 ` Josh Poimboeuf
2019-04-15 16:07 ` Thomas Gleixner
2019-04-15 16:16 ` Josh Poimboeuf
2019-04-15 17:05 ` Andy Lutomirski
2019-04-15 21:22 ` Thomas Gleixner
2019-04-16 11:37 ` Vlastimil Babka
2019-04-16 14:10 ` Thomas Gleixner [this message]
2019-04-16 15:16 ` [patch V5 01/32] mm/slab: Remove " Vlastimil Babka
2019-04-15 21:20 ` [patch V4 01/32] mm/slab: Fix " Thomas Gleixner
2019-04-15 16:21 ` Peter Zijlstra
2019-04-15 16:58 ` [patch V3 " Andy Lutomirski
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=alpine.DEB.2.21.1904161608570.1685@nanos.tec.linutronix.de \
--to=tglx@linutronix.de \
--cc=akpm@linux-foundation.org \
--cc=jpoimboe@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luto@kernel.org \
--cc=penberg@kernel.org \
--cc=rientjes@google.com \
--cc=sean.j.christopherson@intel.com \
--cc=vbabka@suse.cz \
--cc=x86@kernel.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;
as well as URLs for NNTP newsgroup(s).