linux-stable.git/arch, branch v4.2.2

lib/decompressors: use real out buf size for gunzip with kernel

2015-09-29T17:33:37+00:00

commit 2d3862d26e67a59340ba1cf1748196c76c5787de upstream.

When loading x86 64bit kernel above 4GiB with patched grub2, got kernel
gunzip error.

| early console in decompress_kernel
| decompress_kernel:
|       input: [0x807f2143b4-0x807ff61aee]
|      output: [0x807cc00000-0x807f3ea29b] 0x027ea29c: output_len
| boot via startup_64
| KASLR using RDTSC...
|  new output: [0x46fe000000-0x470138cfff] 0x0338d000: output_run_size
|  decompress: [0x46fe000000-0x47007ea29b] <=== [0x807f2143b4-0x807ff61aee]
|
| Decompressing Linux... gz...
|
| uncompression error
|
| -- System halted

the new buffer is at 0x46fe000000ULL, decompressor_gzip is using
0xffffffb901ffffff as out_len.  gunzip in lib/zlib_inflate/inflate.c cap
that len to 0x01ffffff and decompress fails later.

We could hit this problem with crashkernel booting that uses kexec loading
kernel above 4GiB.

We have decompress_* support:
    1. inbuf[]/outbuf[] for kernel preboot.
    2. inbuf[]/flush() for initramfs
    3. fill()/flush() for initrd.
This bug only affect kernel preboot path that use outbuf[].

Add __decompress and take real out_buf_len for gunzip instead of guessing
wrong buf size.

Fixes: 1431574a1c4 (lib/decompressors: fix "no limit" output buffer length)
Signed-off-by: Yinghai Lu 
Cc: Alexandre Courbot 
Cc: Jon Medhurst 
Cc: Stephen Warren 
Cc: "H. Peter Anvin" 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

parisc: Filter out spurious interrupts in PA-RISC irq handler

2015-09-29T17:33:32+00:00

commit b1b4e435e4ef7de77f07bf2a42c8380b960c2d44 upstream.

When detecting a serial port on newer PA-RISC machines (with iosapic) we have a
long way to go to find the right IRQ line, registering it, then registering the
serial port and the irq handler for the serial port. During this phase spurious
interrupts for the serial port may happen which then crashes the kernel because
the action handler might not have been set up yet.

So, basically it's a race condition between the serial port hardware and the
CPU which sets up the necessary fields in the irq sructs. The main reason for
this race is, that we unmask the serial port irqs too early without having set
up everything properly before (which isn't easily possible because we need the
IRQ number to register the serial ports).

This patch is a work-around for this problem. It adds checks to the CPU irq
handler to verify if the IRQ action field has been initialized already. If not,
we just skip this interrupt (which isn't critical for a serial port at bootup).
The real fix would probably involve rewriting all PA-RISC specific IRQ code
(for CPU, IOSAPIC, GSC and EISA) to use IRQ domains with proper parenting of
the irq chips and proper irq enabling along this line.

This bug has been in the PA-RISC port since the beginning, but the crashes
happened very rarely with currently used hardware.  But on the latest machine
which I bought (a C8000 workstation), which uses the fastest CPUs (4 x PA8900,
1GHz) and which has the largest possible L1 cache size (64MB each), the kernel
crashed at every boot because of this race. So, without this patch the machine
would currently be unuseable.

For the record, here is the flow logic:
1. serial_init_chip() in 8250_gsc.c calls iosapic_serial_irq().
2. iosapic_serial_irq() calls txn_alloc_irq() to find the irq.
3. iosapic_serial_irq() calls cpu_claim_irq() to register the CPU irq
4. cpu_claim_irq() unmasks the CPU irq (which it shouldn't!)
5. serial_init_chip() then registers the 8250 port.
Problems:
- In step 4 the CPU irq shouldn't have been registered yet, but after step 5
- If serial irq happens between 4 and 5 have finished, the kernel will crash

Signed-off-by: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

parisc: Use double word condition in 64bit CAS operation

2015-09-29T17:33:31+00:00

commit 1b59ddfcf1678de38a1f8ca9fb8ea5eebeff1843 upstream.

The attached change fixes the condition used in the "sub" instruction.
A double word comparison is needed.  This fixes the 64-bit LWS CAS
operation on 64-bit kernels.

I can now enable 64-bit atomic support in GCC.

Signed-off-by: John David Anglin 
Signed-off-by: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

x86/mm: Initialize pmd_idx in page_table_range_init_count()

2015-09-29T17:33:26+00:00

commit 9962eea9e55f797f05f20ba6448929cab2a9f018 upstream.

The variable pmd_idx is not initialized for the first iteration of the
for loop.

Assign the proper value which indexes the start address.

Fixes: 719272c45b82 'x86, mm: only call early_ioremap_page_table_range_init() once'
Signed-off-by: Minfei Huang 
Cc: tony.luck@intel.com
Cc: wangnan0@huawei.com
Cc: david.vrabel@citrix.com
Reviewed-by: yinghai@kernel.org
Link: http://lkml.kernel.org/r/1436703522-29552-1-git-send-email-mhuang@redhat.com
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

powerpc/mm: Recompute hash value after a failed update

2015-09-29T17:33:25+00:00

commit 36b35d5d807b7e57aff7d08e63de8b17731ee211 upstream.

If we had secondary hash flag set, we ended up modifying hash value in
the updatepp code path. Hence with a failed updatepp we will be using
a wrong hash value for the following hash insert. Fix this by
recomputing hash before insert.

Without this patch we can end up with using wrong slot number in linux
pte. That can result in us missing an hash pte update or invalidate
which can cause memory corruption or even machine check.

Fixes: 6d492ecc6489 ("powerpc/THP: Add code to handle HPTE faults for hugepages")
Signed-off-by: Aneesh Kumar K.V 
Reviewed-by: Paul Mackerras 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/boot: Specify ABI v2 when building an LE boot wrapper

2015-09-29T17:33:25+00:00

commit 655471f54c2e395ba29ae4156ba0f49928177cc1 upstream.

The kernel does it, not the boot wrapper, which breaks with some
cross compilers that still default to ABI v1.

Fixes: 147c05168fc8 ("powerpc/boot: Add support for 64bit little endian wrapper")
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Release DRC when configure_connector fails

2015-09-29T17:33:25+00:00

commit daebaabb5cfbe4a6f09ca0e0f8b7673efc704960 upstream.

Commit f32393c943e2 ("powerpc/pseries: Correct cpu affinity for
dlpar added cpus") moved dlpar_acquire_drc() call to before
dlpar_configure_connector() call in dlpar_cpu_probe(), but missed
to release the DRC if dlpar_configure_connector() failed.
During CPU hotplug, if configure-connector fails for any reason,
then this will result in subsequent CPU hotplug attempts to fail.

Release the acquired DRC if dlpar_configure_connector() call fails
so that the DRC is left in right isolation and allocation state
for the subsequent hotplug operation to succeed.

Fixes: f32393c943e2 ("powerpc/pseries: Correct cpu affinity for dlpar added cpus")
Signed-off-by: Bharata B Rao 
Reviewed-by: Nathan Fontenot 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/powernv/pci-ioda: fix kdump with non-power-of-2 crashkernel=

2015-09-29T17:33:24+00:00

commit fa14486979b3a47307bcdb10f8b5baa875a5cf68 upstream.

The 32-bit TCE table initialization relies on the DMA window having a
size equal to a power of 2 (and checks for it explicitly). But
crashkernel= has no constraint that requires a power-of-2 be specified.
This causes the kdump kernel to fail to boot as none of the PCI devices
(including the disk controller) are successfully initialized.

After this change, the PCI devices successfully set up the 32-bit TCE
table and kdump succeeds.

Fixes: aca6913f5551 ("powerpc/powernv/ioda2: Introduce helpers to allocate TCE pages")
Signed-off-by: Nishanth Aravamudan 
Tested-by: Jan Stancek 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc/powernv/pci-ioda: fix 32-bit TCE table init in kdump kernel

2015-09-29T17:33:24+00:00

commit bb0054552d080dd929907c5925d4bedc8bf6def7 upstream.

When attempting to kdump with the 4.2 kernel, we see for each PCI
device:

 pci 0003:01     : [PE# 000] Assign DMA32 space
 pci 0003:01     : [PE# 000] Setting up 32-bit TCE table at 0..80000000
 pci 0003:01     : [PE# 000] Failed to create 32-bit TCE table, err -22
 PCI: Domain 0004 has 8 available 32-bit DMA segments
 PCI: 4 PE# for a total weight of 70
 pci 0004:01     : [PE# 002] Assign DMA32 space
 pci 0004:01     : [PE# 002] Setting up 32-bit TCE table at 0..80000000
 pci 0004:01     : [PE# 002] Failed to create 32-bit TCE table, err -22
 pci 0004:0d     : [PE# 005] Assign DMA32 space
 pci 0004:0d     : [PE# 005] Setting up 32-bit TCE table at 0..80000000
 pci 0004:0d     : [PE# 005] Failed to create 32-bit TCE table, err -22
 pci 0004:0e     : [PE# 006] Assign DMA32 space
 pci 0004:0e     : [PE# 006] Setting up 32-bit TCE table at 0..80000000
 pci 0004:0e     : [PE# 006] Failed to create 32-bit TCE table, err -22
 pci 0004:10     : [PE# 008] Assign DMA32 space
 pci 0004:10     : [PE# 008] Setting up 32-bit TCE table at 0..80000000
 pci 0004:10     : [PE# 008] Failed to create 32-bit TCE table, err -22

and eventually the kdump kernel fails to boot as none of the PCI devices
(including the disk controller) are successfully initialized.

The EINVAL response is because the DMA window (the 2GB base window) is
larger than the kdump kernel's reserved memory (crashkernel=, in this
case specified to be 1024M). The check in question,

 if ((window_size > memory_hotplug_max()) || !is_power_of_2(window_size))

is a valid sanity check for pnv_pci_ioda2_table_alloc_pages(), so adjust
the caller to pass in a smaller window size if our maximum memory value
is smaller than the DMA window.

After this change, the PCI devices successfully set up the 32-bit TCE
table and kdump succeeds.

The problem was seen on a Firestone machine originally.

Fixes: aca6913f5551 ("powerpc/powernv/ioda2: Introduce helpers to allocate TCE pages")
Signed-off-by: Nishanth Aravamudan 
Reviewed-by: Alexey Kardashevskiy 
[mpe: Coding style pedantry, use u64, change the indentation]
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

powerpc: Uncomment and make enable_kernel_vsx() routine available

2015-09-29T17:33:24+00:00

commit 72cd7b44bc99376b3f3c93cedcd052663fcdf705 upstream.

enable_kernel_vsx() function was commented since anything was using
it. However, vmx-crypto driver uses VSX instructions which are
only available if VSX is enable. Otherwise it rises an exception oops.

This patch uncomment enable_kernel_vsx() routine and makes it available.

Signed-off-by: Leonidas S. Barbosa 
Signed-off-by: Herbert Xu 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman