linux-toradex.git, branch v4.2.4

Linux 4.2.4

2015-10-22T21:49:51+00:00

sched/preempt, powerpc, kvm: Use need_resched() instead of should_resched()

2015-10-22T21:49:35+00:00

commit c56dadf39761a6157239cac39e3988998c994f98 upstream.

Function should_resched() is equal to (!preempt_count() && need_resched()).
In preemptive kernel preempt_count here is non-zero because of vc->lock.

Signed-off-by: Konstantin Khlebnikov 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Alexander Graf 
Cc: Boris Ostrovsky 
Cc: David Vrabel 
Cc: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20150715095203.12246.72922.stgit@buzz
Signed-off-by: Ingo Molnar 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

sched/preempt, xen: Use need_resched() instead of should_resched()

2015-10-22T21:49:35+00:00

commit 0fa2f5cb2b0ecd8d56baa51f35f09aab234eb0bf upstream.

This code is used only when CONFIG_PREEMPT=n and only in non-atomic context:
xen_in_preemptible_hcall is set only in privcmd_ioctl_hypercall().
Thus preempt_count is zero and should_resched() is equal to need_resched().

Signed-off-by: Konstantin Khlebnikov 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Alexander Graf 
Cc: Boris Ostrovsky 
Cc: David Vrabel 
Cc: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20150715095201.12246.49283.stgit@buzz
Signed-off-by: Ingo Molnar 
Cc: Andre Tomt 
Signed-off-by: Greg Kroah-Hartman

3w-9xxx: don't unmap bounce buffered commands

2015-10-22T21:49:35+00:00

commit 15e3d5a285ab9283136dba34bbf72886d9146706 upstream.

3w controller don't dma map small single SGL entry commands but instead
bounce buffer them.  Add a helper to identify these commands and don't
call scsi_dma_unmap for them.

Based on an earlier patch from James Bottomley.

Fixes: 118c85 ("3w-9xxx: fix command completion race")
Reported-by: Tóth Attila 
Tested-by: Tóth Attila 
Signed-off-by: Christoph Hellwig 
Acked-by: Adam Radford 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

sched/preempt: Fix cond_resched_lock() and cond_resched_softirq()

2015-10-22T21:49:35+00:00

commit fe32d3cd5e8eb0f82e459763374aa80797023403 upstream.

These functions check should_resched() before unlocking spinlock/bh-enable:
preempt_count always non-zero => should_resched() always returns false.
cond_resched_lock() worked iff spin_needbreak is set.

This patch adds argument "preempt_offset" to should_resched().

preempt_count offset constants for that:

  PREEMPT_DISABLE_OFFSET  - offset after preempt_disable()
  PREEMPT_LOCK_OFFSET     - offset after spin_lock()
  SOFTIRQ_DISABLE_OFFSET  - offset after local_bh_distable()
  SOFTIRQ_LOCK_OFFSET     - offset after spin_lock_bh()

Signed-off-by: Konstantin Khlebnikov 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Alexander Graf 
Cc: Boris Ostrovsky 
Cc: David Vrabel 
Cc: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Fixes: bdb438065890 ("sched: Extract the basic add/sub preempt_count modifiers")
Link: http://lkml.kernel.org/r/20150715095204.12246.98268.stgit@buzz
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

blk-mq: avoid setting hctx->tags->cpumask before allocation

2015-10-22T21:49:35+00:00

commit 1356aae08338f1c19ce1c67bf8c543a267688fc3 upstream.

When unmapped hw queue is remapped after CPU topology is changed,
hctx->tags->cpumask has to be set after hctx->tags is setup in
blk_mq_map_swqueue(), otherwise it causes null pointer dereference.

Fixes: f26cdc8536 ("blk-mq: Shared tag enhancements")
Signed-off-by: Akinobu Mita 
Cc: Keith Busch 
Cc: Ming Lei 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

mm/slab: fix unexpected index mapping result of kmalloc_size(INDEX_NODE+1)

2015-10-22T21:49:35+00:00

commit 03a2d2a3eafe4015412cf4e9675ca0e2d9204074 upstream.

Commit description is copied from the original post of this bug:

  http://comments.gmane.org/gmane.linux.kernel.mm/135349

Kernels after v3.9 use kmalloc_size(INDEX_NODE + 1) to get the next
larger cache size than the size index INDEX_NODE mapping.  In kernels
3.9 and earlier we used malloc_sizes[INDEX_L3 + 1].cs_size.

However, sometimes we can't get the right output we expected via
kmalloc_size(INDEX_NODE + 1), causing a BUG().

The mapping table in the latest kernel is like:
    index = {0,   1,  2 ,  3,  4,   5,   6,   n}
     size = {0,   96, 192, 8, 16,  32,  64,   2^n}
The mapping table before 3.10 is like this:
    index = {0 , 1 , 2,   3,  4 ,  5 ,  6,   n}
    size  = {32, 64, 96, 128, 192, 256, 512, 2^(n+3)}

The problem on my mips64 machine is as follows:

(1) When configured DEBUG_SLAB && DEBUG_PAGEALLOC && DEBUG_LOCK_ALLOC
    && DEBUG_SPINLOCK, the sizeof(struct kmem_cache_node) will be "150",
    and the macro INDEX_NODE turns out to be "2": #define INDEX_NODE
    kmalloc_index(sizeof(struct kmem_cache_node))

(2) Then the result of kmalloc_size(INDEX_NODE + 1) is 8.

(3) Then "if(size >= kmalloc_size(INDEX_NODE + 1)" will lead to "size
    = PAGE_SIZE".

(4) Then "if ((size >= (PAGE_SIZE >> 3))" test will be satisfied and
    "flags |= CFLGS_OFF_SLAB" will be covered.

(5) if (flags & CFLGS_OFF_SLAB)" test will be satisfied and will go to
    "cachep->slabp_cache = kmalloc_slab(slab_size, 0u)", and the result
    here may be NULL while kernel bootup.

(6) Finally,"BUG_ON(ZERO_OR_NULL_PTR(cachep->slabp_cache));" causes the
    BUG info as the following shows (may be only mips64 has this problem):

This patch fixes the problem of kmalloc_size(INDEX_NODE + 1) and removes
the BUG by adding 'size >= 256' check to guarantee that all necessary
small sized slabs are initialized regardless sequence of slab size in
mapping table.

Fixes: e33660165c90 ("slab: Use common kmalloc_index/kmalloc_size...")
Signed-off-by: Joonsoo Kim 
Reported-by: Liuhailong 
Acked-by: Christoph Lameter 
Cc: Pekka Enberg 
Cc: David Rientjes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

e1000e: Fix tight loop implementation of systime read algorithm

2015-10-22T21:49:35+00:00

commit 37b12910dd11d9ab969f2c310dc9160b7f3e3405 upstream.

Change the algorithm. Read systimel twice and check for overflow.
If there was no overflow, use the first value.
If there was an overflow, read systimeh again and use the second
systimel value.

Signed-off-by: Raanan Avargil 
Tested-by: Aaron Brown 
Signed-off-by: Jeff Kirsher 
Cc: "Jason A. Donenfeld" 
Signed-off-by: Greg Kroah-Hartman

serial: atmel: fix error path of probe function

2015-10-22T21:49:34+00:00

commit 8f1bd8f2ad2358d6a88c115481ff3e69817d1bde upstream.

If atmel_init_gpios fails the port has already been marked as busy (in
line 2629), so this must be undone in the error path.

This bug was introduced because I created the patch that finally
became 722ccf416ac2 ("serial: atmel: fix error handling when
mctrl_gpio_init fails") on top of 3.19 which didn't have commit
6fbb9bdf0f3f ("tty/serial: at91: fix error handling in
atmel_serial_probe()") yet.

Signed-off-by: Uwe Kleine-König 
Fixes: 722ccf416ac2 ("serial: atmel: fix error handling when mctrl_gpio_init fails")
Acked-by: Nicolas Ferre 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: add uart_config entry for PORT_RT2880

2015-10-22T21:49:34+00:00

commit 3c5a0357fdb3a9116a48dbdb0abb91fd23fbff80 upstream.

This adds an entry to the uart_config table for PORT_RT2880
enabling rx/tx FIFOs.  The UART is actually a Palmchip BK-3103
which is found in several devices from Alchemy/RMI, Ralink, and
Sigma Designs.

Signed-off-by: Mans Rullgard 
Signed-off-by: Greg Kroah-Hartman