From: Geert Uytterhoeven <geert+renesas@glider.be>
To: Christoph Lameter <cl@linux.com>,
Pekka Enberg <penberg@kernel.org>,
David Rientjes <rientjes@google.com>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
Andrew Morton <akpm@linux-foundation.org>
Cc: "Tobin C . Harding" <me@tobin.cc>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Geert Uytterhoeven <geert+renesas@glider.be>
Subject: [PATCH] mm/slab: Do not hash pointers when debugging slab
Date: Thu, 7 Dec 2017 11:17:41 +0100 [thread overview]
Message-ID: <1512641861-5113-1-git-send-email-geert+renesas@glider.be> (raw)
If CONFIG_DEBUG_SLAB/CONFIG_DEBUG_SLAB_LEAK are enabled, the slab code
prints extra debug information when e.g. corruption is detected.
This includes pointers, which are not very useful when hashed.
Fix this by using %px to print unhashed pointers instead.
Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
It's been ages I needed the above options. But of course I need them
just after the introduction of address hashing...
---
mm/slab.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/mm/slab.c b/mm/slab.c
index 183e996dde5ff37a..70be5823227dcb3e 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1585,7 +1585,7 @@ static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines)
}
if (cachep->flags & SLAB_STORE_USER) {
- pr_err("Last user: [<%p>](%pSR)\n",
+ pr_err("Last user: [<%px>](%pSR)\n",
*dbg_userword(cachep, objp),
*dbg_userword(cachep, objp));
}
@@ -1621,7 +1621,7 @@ static void check_poison_obj(struct kmem_cache *cachep, void *objp)
/* Mismatch ! */
/* Print header */
if (lines == 0) {
- pr_err("Slab corruption (%s): %s start=%p, len=%d\n",
+ pr_err("Slab corruption (%s): %s start=%px, len=%d\n",
print_tainted(), cachep->name,
realobj, size);
print_objinfo(cachep, objp, 0);
@@ -1650,13 +1650,13 @@ static void check_poison_obj(struct kmem_cache *cachep, void *objp)
if (objnr) {
objp = index_to_obj(cachep, page, objnr - 1);
realobj = (char *)objp + obj_offset(cachep);
- pr_err("Prev obj: start=%p, len=%d\n", realobj, size);
+ pr_err("Prev obj: start=%px, len=%d\n", realobj, size);
print_objinfo(cachep, objp, 2);
}
if (objnr + 1 < cachep->num) {
objp = index_to_obj(cachep, page, objnr + 1);
realobj = (char *)objp + obj_offset(cachep);
- pr_err("Next obj: start=%p, len=%d\n", realobj, size);
+ pr_err("Next obj: start=%px, len=%d\n", realobj, size);
print_objinfo(cachep, objp, 2);
}
}
@@ -2608,7 +2608,7 @@ static void slab_put_obj(struct kmem_cache *cachep,
/* Verify double free bug */
for (i = page->active; i < cachep->num; i++) {
if (get_free_obj(page, i) == objnr) {
- pr_err("slab: double free detected in cache '%s', objp %p\n",
+ pr_err("slab: double free detected in cache '%s', objp %px\n",
cachep->name, objp);
BUG();
}
@@ -2772,7 +2772,7 @@ static inline void verify_redzone_free(struct kmem_cache *cache, void *obj)
else
slab_error(cache, "memory outside object was overwritten");
- pr_err("%p: redzone 1:0x%llx, redzone 2:0x%llx\n",
+ pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n",
obj, redzone1, redzone2);
}
@@ -3078,7 +3078,7 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
if (*dbg_redzone1(cachep, objp) != RED_INACTIVE ||
*dbg_redzone2(cachep, objp) != RED_INACTIVE) {
slab_error(cachep, "double free, or memory outside object was overwritten");
- pr_err("%p: redzone 1:0x%llx, redzone 2:0x%llx\n",
+ pr_err("%px: redzone 1:0x%llx, redzone 2:0x%llx\n",
objp, *dbg_redzone1(cachep, objp),
*dbg_redzone2(cachep, objp));
}
@@ -3091,7 +3091,7 @@ static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
cachep->ctor(objp);
if (ARCH_SLAB_MINALIGN &&
((unsigned long)objp & (ARCH_SLAB_MINALIGN-1))) {
- pr_err("0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n",
+ pr_err("0x%px: not aligned to ARCH_SLAB_MINALIGN=%d\n",
objp, (int)ARCH_SLAB_MINALIGN);
}
return objp;
@@ -4283,7 +4283,7 @@ static void show_symbol(struct seq_file *m, unsigned long address)
return;
}
#endif
- seq_printf(m, "%p", (void *)address);
+ seq_printf(m, "%px", (void *)address);
}
static int leaks_show(struct seq_file *m, void *p)
--
2.7.4
next reply other threads:[~2017-12-07 10:17 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-07 10:17 Geert Uytterhoeven [this message]
2017-12-07 11:13 ` [PATCH] mm/slab: Do not hash pointers when debugging slab Christopher Lameter
2017-12-07 18:43 ` Kees Cook
2017-12-07 20:15 ` Christopher Lameter
2017-12-10 20:45 ` Linus Torvalds
2017-12-11 8:08 ` Geert Uytterhoeven
2017-12-11 12:00 ` Christopher Lameter
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