lists.openwall.net | 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 linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 23 Oct 2014 11:52:03 +0400 From: Roman Gushchin <klamm@...dex-team.ru> To: Jeff Kirsher <jeffrey.t.kirsher@...el.com> Cc: "jesse.brandeburg@...el.com" <jesse.brandeburg@...el.com>, "bruce.w.allan@...el.com" <bruce.w.allan@...el.com>, "carolyn.wyborny@...el.com" <carolyn.wyborny@...el.com>, "donald.c.skidmore@...el.com" <donald.c.skidmore@...el.com>, "gregory.v.rose@...el.com" <gregory.v.rose@...el.com>, "peter.p.waskiewicz.jr@...el.com" <peter.p.waskiewicz.jr@...el.com>, "alexander.h.duyck@...el.com" <alexander.h.duyck@...el.com>, "john.ronciak@...el.com" <john.ronciak@...el.com>, "tushar.n.dave@...el.com" <tushar.n.dave@...el.com>, "davem@...emloft.net" <davem@...emloft.net>, "sassmann@...nic.de" <sassmann@...nic.de>, "gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>, "e1000-devel@...ts.sourceforge.net" <e1000-devel@...ts.sourceforge.net>, "netdev@...r.kernel.org" <netdev@...r.kernel.org>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org> Subject: Re: [PATCH] igb: don't reuse pages with pfmemalloc flag Thank you! Probably we should add it to stable trees too? -- Regards, Roman 22.10.2014, 22:30, "Jeff Kirsher" <jeffrey.t.kirsher@...el.com>: > On Wed, 2014-10-22 at 17:50 +0400, Roman Gushchin wrote: >> Incoming packet is dropped silently by sk_filter(), if the skb was >> allocated from pfmemalloc reserves and the corresponding socket is >> not marked with the SOCK_MEMALLOC flag. >> >> Igb driver allocates pages for DMA with __skb_alloc_page(), which >> calls alloc_pages_node() with the __GFP_MEMALLOC flag. So, in case >> of OOM condition, igb can get pages with pfmemalloc flag set. >> >> If an incoming packet hits the pfmemalloc page and is large enough >> (small packets are copying into the memory, allocated with >> netdev_alloc_skb_ip_align(), so they are not affected), it will be >> dropped. >> >> This behavior is ok under high memory pressure, but the problem is >> that the igb driver reuses these mapped pages. So, packets are still >> dropping even if all memory issues are gone and there is a plenty >> of free memory. >> >> In my case, some TCP sessions hang on a small percentage (< 0.1%) >> of machines days after OOMs. >> >> Fix this by avoiding reuse of such pages. >> >> Signed-off-by: Roman Gushchin <klamm@...dex-team.ru> >> --- >> drivers/net/ethernet/intel/igb/igb_main.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) > > Thanks Roman, I have added you patch to my queue. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists