lwn.git, branch v3.10.63

Linux 3.10.63

2014-12-16T17:09:56+00:00

ALSA: usb-audio: Don't resubmit pending URBs at MIDI error recovery

2014-12-16T17:09:43+00:00

commit 66139a48cee1530c91f37c145384b4ee7043f0b7 upstream. In snd_usbmidi_error_timer(), the driver tries to resubmit MIDI input URBs to reactivate the MIDI stream, but this causes the error when some of URBs are still pending like: WARNING: CPU: 0 PID: 0 at ../drivers/usb/core/urb.c:339 usb_submit_urb+0x5f/0x70() URB ef705c40 submitted while active CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.16.6-2-desktop #1 Hardware name: FOXCONN TPS01/TPS01, BIOS 080015 03/23/2010 c0984bfa f4009ed4 c078deaf f4009ee4 c024c884 c09a135c f4009f00 00000000 c0984bfa 00000153 c061ac4f c061ac4f 00000009 00000001 ef705c40 e854d1c0 f4009eec c024c8d3 00000009 f4009ee4 c09a135c f4009f00 f4009f04 c061ac4f Call Trace: [] try_stack_unwind+0x156/0x170 [] dump_trace+0x5a/0x1b0 [] show_trace_log_lvl+0x46/0x50 [] show_stack_log_lvl+0x51/0xe0 [] show_stack+0x27/0x50 [] dump_stack+0x45/0x65 [] warn_slowpath_common+0x84/0xa0 [] warn_slowpath_fmt+0x33/0x40 [] usb_submit_urb+0x5f/0x70 [] snd_usbmidi_submit_urb+0x14/0x60 [snd_usbmidi_lib] [] snd_usbmidi_error_timer+0x6a/0xa0 [snd_usbmidi_lib] [] call_timer_fn+0x30/0x130 [] run_timer_softirq+0x1c2/0x260 [] __do_softirq+0xc3/0x270 [] do_softirq_own_stack+0x22/0x30 [] irq_exit+0x8d/0xa0 [] smp_apic_timer_interrupt+0x38/0x50 [] apic_timer_interrupt+0x34/0x3c [] cpuidle_enter_state+0x3e/0xd0 [] cpu_idle_loop+0x29d/0x3e0 [] cpu_startup_entry+0x53/0x60 [] start_kernel+0x415/0x41a For avoiding these errors, check the pending URBs and skip resubmitting such ones. Reported-and-tested-by: Stefan Seyfried Acked-by: Clemens Ladisch Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

powerpc: 32 bit getcpu VDSO function uses 64 bit instructions

2014-12-16T17:09:43+00:00

commit 152d44a853e42952f6c8a504fb1f8eefd21fd5fd upstream. I used some 64 bit instructions when adding the 32 bit getcpu VDSO function. Fix it. Fixes: 18ad51dd342a ("powerpc: Add VDSO version of getcpu") Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

ARM: sched_clock: Load cycle count after epoch stabilizes

2014-12-16T17:09:43+00:00

commit 336ae1180df5f69b9e0fb6561bec01c5f64361cf upstream. There is a small race between when the cycle count is read from the hardware and when the epoch stabilizes. Consider this scenario: CPU0 CPU1 ---- ---- cyc = read_sched_clock() cyc_to_sched_clock() update_sched_clock() ... cd.epoch_cyc = cyc; epoch_cyc = cd.epoch_cyc; ... epoch_ns + cyc_to_ns((cyc - epoch_cyc) The cyc on cpu0 was read before the epoch changed. But we calculate the nanoseconds based on the new epoch by subtracting the new epoch from the old cycle count. Since epoch is most likely larger than the old cycle count we calculate a large number that will be converted to nanoseconds and added to epoch_ns, causing time to jump forward too much. Fix this problem by reading the hardware after the epoch has stabilized. Cc: Russell King Signed-off-by: Stephen Boyd Signed-off-by: John Stultz Signed-off-by: Greg Kroah-Hartman

igb: bring link up when PHY is powered up

2014-12-16T17:09:43+00:00

commit aec653c43b0c55667355e26d7de1236bda9fb4e3 upstream. Call igb_setup_link() when the PHY is powered up. Signed-off-by: Todd Fujinaka Reported-by: Jeff Westfahl Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher Cc: Vincent Donnefort Signed-off-by: Greg Kroah-Hartman

ext2: Fix oops in ext2_get_block() called from ext2_quota_write()

2014-12-16T17:09:43+00:00

commit df4e7ac0bb70abc97fbfd9ef09671fc084b3f9db upstream. ext2_quota_write() doesn't properly setup bh it passes to ext2_get_block() and thus we hit assertion BUG_ON(maxblocks == 0) in ext2_get_blocks() (or we could actually ask for mapping arbitrary number of blocks depending on whatever value was on stack). Fix ext2_quota_write() to properly fill in number of blocks to map. Reviewed-by: "Theodore Ts'o" Reviewed-by: Christoph Hellwig Reported-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman

nEPT: Nested INVEPT

2014-12-16T17:09:43+00:00

commit bfd0a56b90005f8c8a004baf407ad90045c2b11e upstream. If we let L1 use EPT, we should probably also support the INVEPT instruction. In our current nested EPT implementation, when L1 changes its EPT table for L2 (i.e., EPT12), L0 modifies the shadow EPT table (EPT02), and in the course of this modification already calls INVEPT. But if last level of shadow page is unsync not all L1's changes to EPT12 are intercepted, which means roots need to be synced when L1 calls INVEPT. Global INVEPT should not be different since roots are synced by kvm_mmu_load() each time EPTP02 changes. Reviewed-by: Xiao Guangrong Signed-off-by: Nadav Har'El Signed-off-by: Jun Nakajima Signed-off-by: Xinhao Xu Signed-off-by: Yang Zhang Signed-off-by: Gleb Natapov Signed-off-by: Paolo Bonzini [bwh: Backported to 3.2: - Adjust context, filename - Simplify handle_invept() as recommended by Paolo - nEPT is not supported so we always raise #UD] Signed-off-by: Ben Hutchings Cc: Vinson Lee Signed-off-by: Greg Kroah-Hartman

net: sctp: use MAX_HEADER for headroom reserve in output path

2014-12-16T17:09:43+00:00

[ Upstream commit 9772b54c55266ce80c639a80aa68eeb908f8ecf5 ] To accomodate for enough headroom for tunnels, use MAX_HEADER instead of LL_MAX_HEADER. Robert reported that he has hit after roughly 40hrs of trinity an skb_under_panic() via SCTP output path (see reference). I couldn't reproduce it from here, but not using MAX_HEADER as elsewhere in other protocols might be one possible cause for this. In any case, it looks like accounting on chunks themself seems to look good as the skb already passed the SCTP output path and did not hit any skb_over_panic(). Given tunneling was enabled in his .config, the headroom would have been expanded by MAX_HEADER in this case. Reported-by: Robert Święcki Reference: https://lkml.org/lkml/2014/12/1/507 Fixes: 594ccc14dfe4d ("[SCTP] Replace incorrect use of dev_alloc_skb with alloc_skb in sctp_packet_transmit().") Signed-off-by: Daniel Borkmann Acked-by: Vlad Yasevich Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: mvneta: fix Tx interrupt delay

2014-12-16T17:09:43+00:00

[ Upstream commit aebea2ba0f7495e1a1c9ea5e753d146cb2f6b845 ] The mvneta driver sets the amount of Tx coalesce packets to 16 by default. Normally that does not cause any trouble since the driver uses a much larger Tx ring size (532 packets). But some sockets might run with very small buffers, much smaller than the equivalent of 16 packets. This is what ping is doing for example, by setting SNDBUF to 324 bytes rounded up to 2kB by the kernel. The problem is that there is no documented method to force a specific packet to emit an interrupt (eg: the last of the ring) nor is it possible to make the NIC emit an interrupt after a given delay. In this case, it causes trouble, because when ping sends packets over its raw socket, the few first packets leave the system, and the first 15 packets will be emitted without an IRQ being generated, so without the skbs being freed. And since the socket's buffer is small, there's no way to reach that amount of packets, and the ping ends up with "send: no buffer available" after sending 6 packets. Running with 3 instances of ping in parallel is enough to hide the problem, because with 6 packets per instance, that's 18 packets total, which is enough to grant a Tx interrupt before all are sent. The original driver in the LSP kernel worked around this design flaw by using a software timer to clean up the Tx descriptors. This timer was slow and caused terrible network performance on some Tx-bound workloads (such as routing) but was enough to make tools like ping work correctly. Instead here, we simply set the packet counts before interrupt to 1. This ensures that each packet sent will produce an interrupt. NAPI takes care of coalescing interrupts since the interrupt is disabled once generated. No measurable performance impact nor CPU usage were observed on small nor large packets, including when saturating the link on Tx, and this fixes tools like ping which rely on too small a send buffer. If one wants to increase this value for certain workloads where it is safe to do so, "ethtool -C $dev tx-frames" will override this default setting. This fix needs to be applied to stable kernels starting with 3.10. Tested-By: Maggie Mae Roxas Signed-off-by: Willy Tarreau Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

rtnetlink: release net refcnt on error in do_setlink()

2014-12-16T17:09:42+00:00

[ Upstream commit e0ebde0e131b529fd721b24f62872def5ec3718c ] rtnl_link_get_net() holds a reference on the 'struct net', we need to release it in case of error. CC: Eric W. Biederman Fixes: b51642f6d77b ("net: Enable a userns root rtnl calls that are safe for unprivilged users") Signed-off-by: Nicolas Dichtel Reviewed-by: "Eric W. Biederman" Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman