user/sven/linux.git/include, branch v3.10.33

ipc,mqueue: remove limits for the amount of system-wide queues

2014-03-07T05:30:12Z

commit f3713fd9cff733d9df83116422d8e4af6e86b2bb upstream. Commit 93e6f119c0ce ("ipc/mqueue: cleanup definition names and locations") added global hardcoded limits to the amount of message queues that can be created. While these limits are per-namespace, reality is that it ends up breaking userspace applications. Historically users have, at least in theory, been able to create up to INT_MAX queues, and limiting it to just 1024 is way too low and dramatic for some workloads and use cases. For instance, Madars reports: "This update imposes bad limits on our multi-process application. As our app uses approaches that each process opens its own set of queues (usually something about 3-5 queues per process). In some scenarios we might run up to 3000 processes or more (which of-course for linux is not a problem). Thus we might need up to 9000 queues or more. All processes run under one user." Other affected users can be found in launchpad bug #1155695: https://bugs.launchpad.net/ubuntu/+source/manpages/+bug/1155695 Instead of increasing this limit, revert it entirely and fallback to the original way of dealing queue limits -- where once a user's resource limit is reached, and all memory is used, new queues cannot be created. Signed-off-by: Davidlohr Bueso Reported-by: Madars Vitolins Acked-by: Doug Ledford Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

net: ip, ipv6: handle gso skbs in forwarding path

2014-03-07T05:30:05Z

commit fe6cc55f3a9a053482a76f5a6b2257cee51b4663 upstream. Marcelo Ricardo Leitner reported problems when the forwarding link path has a lower mtu than the incoming one if the inbound interface supports GRO. Given: Host R1 R2 Host sends tcp stream which is routed via R1 and R2. R1 performs GRO. In this case, the kernel will fail to send ICMP fragmentation needed messages (or pkt too big for ipv6), as GSO packets currently bypass dstmtu checks in forward path. Instead, Linux tries to send out packets exceeding the mtu. When locking route MTU on Host (i.e., no ipv4 DF bit set), R1 does not fragment the packets when forwarding, and again tries to send out packets exceeding R1-R2 link mtu. This alters the forwarding dstmtu checks to take the individual gso segment lengths into account. For ipv6, we send out pkt too big error for gso if the individual segments are too big. For ipv4, we either send icmp fragmentation needed, or, if the DF bit is not set, perform software segmentation and let the output path create fragments when the packet is leaving the machine. It is not 100% correct as the error message will contain the headers of the GRO skb instead of the original/segmented one, but it seems to work fine in my (limited) tests. Eric Dumazet suggested to simply shrink mss via ->gso_size to avoid sofware segmentation. However it turns out that skb_segment() assumes skb nr_frags is related to mss size so we would BUG there. I don't want to mess with it considering Herbert and Eric disagree on what the correct behavior should be. Hannes Frederic Sowa notes that when we would shrink gso_size skb_segment would then also need to deal with the case where SKB_MAX_FRAGS would be exceeded. This uses sofware segmentation in the forward path when we hit ipv4 non-DF packets and the outgoing link mtu is too small. Its not perfect, but given the lack of bug reports wrt. GRO fwd being broken this is a rare case anyway. Also its not like this could not be improved later once the dust settles. Acked-by: Herbert Xu Reported-by: Marcelo Ricardo Leitner Signed-off-by: Florian Westphal Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: core: introduce netif_skb_dev_features

2014-03-07T05:30:05Z

commit d206940319c41df4299db75ed56142177bb2e5f6 upstream. Will be used by upcoming ipv4 forward path change that needs to determine feature mask using skb->dst->dev instead of skb->dev. Signed-off-by: Florian Westphal Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: add and use skb_gso_transport_seglen()

2014-03-07T05:30:05Z

commit de960aa9ab4decc3304959f69533eef64d05d8e8 upstream. [ no skb_gso_seglen helper in 3.10, leave tbf alone ] This moves part of Eric Dumazets skb_gso_seglen helper from tbf sched to skbuff core so it may be reused by upcoming ip forwarding path patch. Signed-off-by: Florian Westphal Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

can: add destructor for self generated skbs

2014-03-07T05:30:03Z

[ Upstream commit 0ae89beb283a0db5980d1d4781c7d7be2f2810d6 ] Self generated skbuffs in net/can/bcm.c are setting a skb->sk reference but no explicit destructor which is enforced since Linux 3.11 with commit 376c7311bdb6 (net: add a temporary sanity check in skb_orphan()). This patch adds some helper functions to make sure that a destructor is properly defined when a sock reference is assigned to a CAN related skb. To create an unshared skb owned by the original sock a common helper function has been introduced to replace open coded functions to create CAN echo skbs. Signed-off-by: Oliver Hartkopp Tested-by: Andre Naujoks Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

compiler/gcc4: Make quirk for asm_volatile_goto() unconditional

2014-02-22T20:41:29Z

commit a9f180345f5378ac87d80ed0bea55ba421d83859 upstream. I started noticing problems with KVM guest destruction on Linux 3.12+, where guest memory wasn't being cleaned up. I bisected it down to the commit introducing the new 'asm goto'-based atomics, and found this quirk was later applied to those. Unfortunately, even with GCC 4.8.2 (which ostensibly fixed the known 'asm goto' bug) I am still getting some kind of miscompilation. If I enable the asm_volatile_goto quirk for my compiler, KVM guests are destroyed correctly and the memory is cleaned up. So make the quirk unconditional for now, until bug is found and fixed. Suggested-by: Linus Torvalds Signed-off-by: Steven Noonan Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Jakub Jelinek Cc: Richard Henderson Cc: Andrew Morton Cc: Oleg Nesterov Link: http://lkml.kernel.org/r/1392274867-15236-1-git-send-email-steven@uplinklabs.net Link: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

ore: Fix wrong math in allocation of per device BIO

2014-02-13T21:48:00Z

commit aad560b7f63b495f48a7232fd086c5913a676e6f upstream. At IO preparation we calculate the max pages at each device and allocate a BIO per device of that size. The calculation was wrong on some unaligned corner cases offset/length combination and would make prepare return with -ENOMEM. This would be bad for pnfs-objects that would in that case IO through MDS. And fatal for exofs were it would fail writes with EIO. Fix it by doing the proper math, that will work in all cases. (I ran a test with all possible offset/length combinations this time round). Also when reading we do not need to allocate for the parity units since we jump over them. Also lower the max_io_length to take into account the parity pages so not to allocate BIOs bigger than PAGE_SIZE Signed-off-by: Boaz Harrosh Signed-off-by: Greg Kroah-Hartman

fs/compat: fix lookup_dcookie() parameter handling

2014-02-13T21:48:00Z

commit d8d14bd09cddbaf0168d61af638455a26bd027ff upstream. Commit d5dc77bfeeab ("consolidate compat lookup_dcookie()") coverted all architectures to the new compat_sys_lookup_dcookie() syscall. The "len" paramater of the new compat syscall must have the type compat_size_t in order to enforce zero extension for architectures where the ABI requires that the caller of a function performed zero and/or sign extension to 64 bit of all parameters. Signed-off-by: Heiko Carstens Cc: Al Viro Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Hendrik Brueckner Cc: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

fs/compat: fix parameter handling for compat readv/writev syscalls

2014-02-13T21:48:00Z

commit dfd948e32af2e7b28bcd7a490c0a30d4b8df2a36 upstream. We got a report that the pwritev syscall does not work correctly in compat mode on s390. It turned out that with commit 72ec35163f9f ("switch compat readv/writev variants to COMPAT_SYSCALL_DEFINE") we lost the zero extension of a couple of syscall parameters because the some parameter types haven't been converted from unsigned long to compat_ulong_t. This is needed for architectures where the ABI requires that the caller of a function performed zero and/or sign extension to 64 bit of all parameters. Signed-off-by: Heiko Carstens Cc: Al Viro Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Hendrik Brueckner Cc: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

mm/page-writeback.c: do not count anon pages as dirtyable memory

2014-02-13T21:48:00Z

commit a1c3bfb2f67ef766de03f1f56bdfff9c8595ab14 upstream. The VM is currently heavily tuned to avoid swapping. Whether that is good or bad is a separate discussion, but as long as the VM won't swap to make room for dirty cache, we can not consider anonymous pages when calculating the amount of dirtyable memory, the baseline to which dirty_background_ratio and dirty_ratio are applied. A simple workload that occupies a significant size (40+%, depending on memory layout, storage speeds etc.) of memory with anon/tmpfs pages and uses the remainder for a streaming writer demonstrates this problem. In that case, the actual cache pages are a small fraction of what is considered dirtyable overall, which results in an relatively large portion of the cache pages to be dirtied. As kswapd starts rotating these, random tasks enter direct reclaim and stall on IO. Only consider free pages and file pages dirtyable. Signed-off-by: Johannes Weiner Reported-by: Tejun Heo Tested-by: Tejun Heo Reviewed-by: Rik van Riel Cc: Mel Gorman Cc: Wu Fengguang Reviewed-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman