1. 04 Apr, 2017 2 commits
    • Michal Hocko's avatar
      mm/huge_memory.c: fix up "mm/huge_memory.c: respect FOLL_FORCE/FOLL_COW for thp" backport · 2ea68951
      Michal Hocko authored
      This is a stable follow up fix for an incorrect backport. The issue is
      not present in the upstream kernel.
      
      Miroslav has noticed the following splat when testing my 3.2 forward
      port of 8310d48b ("mm/huge_memory.c: respect FOLL_FORCE/FOLL_COW for
      thp") to 3.12:
      
      BUG: Bad page state in process a.out  pfn:26400
      page:ffffea000085e000 count:0 mapcount:1 mapping:          (null) index:0x7f049d600
      page flags: 0x1fffff80108018(uptodate|dirty|head|swapbacked)
      page dumped because: nonzero mapcount
      [iii]
      CPU: 2 PID: 5926 Comm: a.out Tainted: G            E    3.12.61-0-default #1
      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
       0000000000000000 ffffffff81515830 ffffea000085e000 ffffffff81800ad7
       ffffffff815118a5 ffffea000085e000 0000000000000000 000fffff80000000
       ffffffff81140f18 fff000007c000000 ffffea000085e000 0000000000000009
      Call Trace:
       [<ffffffff8100475d>] dump_trace+0x7d/0x2d0
       [<ffffffff81004a44>] show_stack_log_lvl+0x94/0x170
       [<ffffffff81005ce1>] show_stack+0x21/0x50
       [<ffffffff81515830>] dump_stack+0x5d/0x78
       [<ffffffff815118a5>] bad_page.part.67+0xe8/0x102
       [<ffffffff81140f18>] free_pages_prepare+0x198/0x1b0
       [<ffffffff81141275>] __free_pages_ok+0x15/0xd0
       [<ffffffff8116444c>] __access_remote_vm+0x7c/0x1e0
       [<ffffffff81205afb>] mem_rw.isra.13+0x14b/0x1a0
       [<ffffffff811a3b18>] vfs_write+0xb8/0x1e0
       [<ffffffff811a469b>] SyS_pwrite64+0x6b/0xa0
       [<ffffffff81523b49>] system_call_fastpath+0x16/0x1b
       [<00007f049da18573>] 0x7f049da18572
      
      The problem is that the original 3.2 backport didn't return NULL page on
      the FOLL_COW page and so the page got reused.
      Reported-and-tested-by: default avatarMiroslav Beneš <mbenes@suse.com>
      Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      2ea68951
    • Eric Dumazet's avatar
      ipv4: keep skb->dst around in presence of IP options · 6892986c
      Eric Dumazet authored
      Upstream commit 34b2cef2
      ("ipv4: keep skb->dst around in presence of IP options") incorrectly
      root caused commit d826eb14 ("ipv4: PKTINFO doesnt need dst
      reference") as bug origin.
      
      This patch should fix the issue for 3.2.xx stable kernels, since IPv4
      options seem to get more traction these days, after years of oblivion ;)
      
      Fixes: f84af32c ("net: ip_queue_rcv_skb() helper"))
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarAnarcheuz Fritz <anarcheuz@gmail.com>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      6892986c
  2. 16 Mar, 2017 38 commits