lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:   Fri,  7 Sep 2018 13:43:34 +0200
From:   Michal Hocko <>
To:     <>
Cc:     Vlastimil Babka <>,
        Andrew Morton <>,
        David Rientjes <>,
        Mel Gorman <>,
        LKML <>,
        Michal Hocko <>
Subject: [RFC PATCH] mm, page_alloc: drop should_suppress_show_mem

From: Michal Hocko <>

should_suppress_show_mem has been introduced to reduce the overhead of
show_mem on large NUMA systems. Things have changed since then though.
Namely c78e93630d15 ("mm: do not walk all of system memory during
show_mem") has reduced the overhead considerably.

Moreover warn_alloc_show_mem clears SHOW_MEM_FILTER_NODES when called
from the IRQ context already so we are not printing per node stats.

Remove should_suppress_show_mem because we are losing potentially
interesting information about allocation failures. We have seen a bug
report where system gets unresponsive under memory pressure and there
is only
kernel: [2032243.696888] qlge 0000:8b:00.1 ql1: Could not get a page chunk, i=8, clean_idx =200 .
kernel: [2032243.710725] swapper/7: page allocation failure: order:1, mode:0x1084120(GFP_ATOMIC|__GFP_COLD|__GFP_COMP)

without an additional information for debugging. It would be great to
see the state of the page allocator at the moment.

Signed-off-by: Michal Hocko <>
 mm/page_alloc.c | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 89d2a2ab3fe6..025f23dc282e 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3366,26 +3366,12 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
 	return NULL;
- * Large machines with many possible nodes should not always dump per-node
- * meminfo in irq context.
- */
-static inline bool should_suppress_show_mem(void)
-	bool ret = false;
-#if NODES_SHIFT > 8
-	ret = in_interrupt();
-	return ret;
 static void warn_alloc_show_mem(gfp_t gfp_mask, nodemask_t *nodemask)
 	unsigned int filter = SHOW_MEM_FILTER_NODES;
 	static DEFINE_RATELIMIT_STATE(show_mem_rs, HZ, 1);
-	if (should_suppress_show_mem() || !__ratelimit(&show_mem_rs))
+	if (!__ratelimit(&show_mem_rs))

Powered by blists - more mailing lists