SNB graphics devices have a bug that prevent them from accessing certain
memory ranges, namely anything below 1M and in the pages listed in the
table. So reserve those at boot if set detect a SNB gfx device on the
CPU to avoid GPU hangs.
Stephane Marchesin had a similar patch to the page allocator awhile
back, but rather than reserving pages up front, it leaked them at
allocation time.
[ hpa: made a number of stylistic changes, marked arrays as static
const, and made less verbose; use "memblock=debug" for full
verbosity. ]
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
NFS4ERR_DELAY is a legal reply when we call DESTROY_SESSION. It
usually means that the server is busy handling an unfinished RPC
request. Just sleep for a second and then retry.
We also need to be able to handle the NFS4ERR_BACK_CHAN_BUSY return
value. If the NFS server has outstanding callbacks, we just want to
similarly sleep & retry.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Ensure that any setattr and getattr requests for junctions and/or
mountpoints are sent to the server. Ever since commit 0ec26fd0698 (vfs: automount should ignore LOOKUP_FOLLOW), we have
silently dropped any setattr requests to a server-side mountpoint.
For referrals, we have silently dropped both getattr and setattr
requests.
This patch restores the original behaviour for setattr on mountpoints,
and tries to do the same for referrals, provided that we have a
filehandle...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
It has been reported that running this driver on some Samsung laptops
with EFI can cause those machines to become bricked as detailed in the
following report,
There have also been reports of this driver causing Machine Check
Exceptions on recent EFI-enabled Samsung laptops,
https://bugzilla.kernel.org/show_bug.cgi?id=47121
So disable it if booting from EFI since this driver relies on
grovelling around in the BIOS memory map which isn't going to work.
Cc: Corentin Chary <corentincj@iksaif.net> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Colin Ian King <colin.king@canonical.com> Cc: Steve Langasek <steve.langasek@canonical.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Originally 'efi_enabled' indicated whether a kernel was booted from
EFI firmware. Over time its semantics have changed, and it now
indicates whether or not we are booted on an EFI machine with
bit-native firmware, e.g. 64-bit kernel with 64-bit firmware.
The immediate motivation for this patch is the bug report at,
which details how running a platform driver on an EFI machine that is
designed to run under BIOS can cause the machine to become
bricked. Also, the following report,
https://bugzilla.kernel.org/show_bug.cgi?id=47121
details how running said driver can also cause Machine Check
Exceptions. Drivers need a new means of detecting whether they're
running on an EFI machine, as sadly the expression,
if (!efi_enabled)
hasn't been a sufficient condition for quite some time.
Users actually want to query 'efi_enabled' for different reasons -
what they really want access to is the list of available EFI
facilities.
For instance, the x86 reboot code needs to know whether it can invoke
the ResetSystem() function provided by the EFI runtime services, while
the ACPI OSL code wants to know whether the EFI config tables were
mapped successfully. There are also checks in some of the platform
driver code to simply see if they're running on an EFI machine (which
would make it a bad idea to do BIOS-y things).
This patch is a prereq for the samsung-laptop fix patch.
Cc: David Airlie <airlied@linux.ie> Cc: Corentin Chary <corentincj@iksaif.net> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Olof Johansson <olof@lixom.net> Cc: Peter Jones <pjones@redhat.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: Steve Langasek <steve.langasek@canonical.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Konrad Rzeszutek Wilk <konrad@kernel.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
[bwh: Backported to 3.2:
- Adjust context (a lot)
- Add efi_is_native() function from commit 5189c2a7c776
('x86: efi: Turn off efi_enabled after setup on mixed fw/kernel')
- Make efi_init() bail out when booted non-native, as it would previously
not be called in this case
- Drop inapplicable changes to start_kernel()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
For non-snoop mode, we fiddle with the page attributes of CORB/RIRB
and the position buffer, but also the ring buffers. The problem is
that the current code blindly assumes that the buffer is contiguous.
However, the ring buffers may be SG-buffers, thus a wrong vmapped
address is passed there, leading to Oops.
Running AIO is pinning inode in memory using file reference. Once AIO
is completed using aio_complete(), file reference is put and inode can
be freed from memory. So we have to be sure that calling aio_complete()
is the last thing we do with the inode.
CC: xfs@oss.sgi.com CC: Ben Myers <bpm@sgi.com> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The IOMMU may stop processing page translations due to a perceived lack
of credits for writing upstream peripheral page service request (PPR)
or event logs. If the L2B miscellaneous clock gating feature is enabled
the IOMMU does not properly register credits after the log request has
completed, leading to a potential system hang.
BIOSes are supposed to disable L2B micellaneous clock gating by setting
L2_L2B_CK_GATE_CONTROL[CKGateL2BMiscDisable](D0F2xF4_x90[2]) = 1b. This
patch corrects that for those which do not enable this workaround.
I get the following warning every day with v3.7, once or
twice a day:
[ 2235.186027] WARNING: at /mnt/sda7/kernel/linux/arch/x86/kernel/apic/ipi.c:109 default_send_IPI_mask_logical+0x2f/0xb8()
As explained by Linus as well:
|
| Once we've done the "list_add_rcu()" to add it to the
| queue, we can have (another) IPI to the target CPU that can
| now see it and clear the mask.
|
| So by the time we get to actually send the IPI, the mask might
| have been cleared by another IPI.
|
This patch also fixes a system hang problem, if the data->cpumask
gets cleared after passing this point:
if (WARN_ONCE(!mask, "empty IPI mask"))
return;
then the problem in commit 83d349f35e1a ("x86: don't send an IPI to
the empty set of CPU's") will happen again.
Signed-off-by: Wang YanQing <udknight@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Jan Beulich <jbeulich@suse.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: peterz@infradead.org Cc: mina86@mina86.org Cc: srivatsa.bhat@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/20130126075357.GA3205@udknight
[ Tidied up the changelog and the comment in the code. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit 23caaf19b11e (ALSA: usb-mixer: Add support for Audio Class v2.0)
forgot to adjust the length check for UAC 2.0 feature unit descriptors.
This would make the code abort on encountering a feature unit without
per-channel controls, and thus prevented the driver to work with any
device having such a unit, such as the RME Babyface or Fireface UCX.
Reported-by: Florian Hanisch <fhanisch@uni-potsdam.de> Tested-by: Matthew Robbetts <wingfeathera@gmail.com> Tested-by: Michael Beer <beerml@sigma6audio.de> Cc: Daniel Mack <daniel@caiaq.de> Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
At the moment the MSR driver only relies upon file system
checks. This means that anything as root with any capability set
can write to MSRs. Historically that wasn't very interesting but
on modern processors the MSRs are such that writing to them
provides several ways to execute arbitary code in kernel space.
Sample code and documentation on doing this is circulating and
MSR attacks are used on Windows 64bit rootkits already.
In the Linux case you still need to be able to open the device
file so the impact is fairly limited and reduces the security of
some capability and security model based systems down towards
that of a generic "root owns the box" setup.
Therefore they should require CAP_SYS_RAWIO to prevent an
elevation of capabilities. The impact of this is fairly minimal
on most setups because they don't have heavy use of
capabilities. Those using SELinux, SMACK or AppArmor rules might
want to consider if their rulesets on the MSR driver could be
tighter.
Signed-off-by: Alan Cox <alan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If one (but not both) allocations of p->chunks[].kpage[]
in radeon_cs_parser_init fail, the error path will free
the successfully allocated page, but leave a stale pointer
value in the kpage[] field. This will later cause a
double-free when radeon_cs_parser_fini is called.
This patch fixes the issue by forcing both pointers to NULL
after kfree in the error path.
The circumstances under which the problem happens are very
rare. The card must be AGP and the system must run out of
kmalloc area just at the right time so that one allocation
succeeds, while the other fails.
Signed-off-by: Ilija Hadzic <ihadzic@research.bell-labs.com> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[bwh: Backported to 3.2: s/p->chunk_ib_idx/i/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Useful for statistics or on overflowing bug reports to keep things all
lined up.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
DMAR support on g4x/gm45 integrated gpus seems to be totally busted.
So don't bother, but instead disable it by default to allow distros to
unconditionally enable DMAR support.
v2: Actually wire up the right quirk entry, spotted by Adam Jackson.
Note that according to intel marketing materials only g45 and gm45
support DMAR/VT-d. So we have reports for all relevant gen4 pci ids by
now. Still, keep all the other gen4 ids in the quirk table in case the
marketing stuff confused me again, which would not be the first time.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=51921
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=538163
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=538163 Cc: Adam Jackson <ajax@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Acked-By: David Woodhouse <David.Woodhouse@intel.com> Tested-by: stathis <stathis@npcglib.org> Tested-by: Mihai Moldovan <ionic@ionic.de> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On SNB, if bit 13 of GFX_MODE, Flush TLB Invalidate Mode, is not set to 1,
the hardware can not program the scanline values. Those scanline values
then control when the signal is sent from the display engine to the render
ring for MI_WAIT_FOR_EVENTs. Note setting this bit means that TLB
invalidations must be performed explicitly through the appropriate bits
being set in PIPE_CONTROL.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52311 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Ben Widawsky <ben@bwidawsk.net> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: s/_MASKED_BIT/GFX_MODE/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This is a required workarounds for all products, especially on gen6+
where it causes the command streamer to fail to parse instructions
following a WAIT_FOR_EVENT. We use WAIT_FOR_EVENT for synchronising
between the GPU and the display engines, and so this bit being unset may
cause hangs.
References: https://bugzilla.kernel.org/show_bug.cgi?id=52311 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2:
- Adjust context
- s/_MASKED_BIT/GFX_MODE/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Older specs claimed this was bit 11, but newer specs and the actual
simulator code say it was bit 12. Regardless, we don't use MI_FLUSH,
or try to enable it any more.
Signed-off-by: Eric Anholt <eric@anholt.net> Reviewed-by: Kenneth Graunke <kenneth@whitecape.org> Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Anyone trying to use this bit, please read all the relevant
discussions, it's epic.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We have always been using the wrong bit -- it's bit 12. However, the
bit also doesn't do anything -- hardware has always accepted the
MI_FLUSH command even when it was specced not to.
Given that there is only one MI_FLUSH emitted in all of the driver
stack on gen6+ (in i965_video.c of the 2d driver, and it should be
using other code to do its flush instead), just remove the MI_FLUSH
enable instead of trying to fix it.
Signed-off-by: Eric Anholt <eric@anholt.net> Reviewed-by: Kenneth Graunke <kenneth@whitecape.org> Reviewed-by: Ben Widawsky <ben@bwidawsk.net> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Chain swapping should only be enabled when the EEPROM chainmask is set to 5,
regardless of what the runtime chainmask is.
Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: keep the special case for AR_SREV_9462 here] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Update efi_call_phys_prelog to install an identity mapping of all available
memory. This corrects a bug on very large systems with more then 512 GB in
which bios would not be able to access addresses above not in the mapping.
On hardware reintialization reference count of
already existing timers would be increased again.
This leads to problems on module unloading.
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com> Reviewed-by: Hante Meuleman <meuleman@broadcom.com> Reviewed-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Piotr Haber <phaber@broadcom.com> Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When the next beacon is sent, the ath_buf from the previous run is reused.
If getting a new beacon from mac80211 fails, bf->bf_mpdu is not reset, yet
the skb is freed, leading to a double-free on the next beacon tx attempt,
resulting in a system crash.
Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On AR9300 the rx FIFO needs to be empty during reset to ensure that no
further DMA activity is generated, otherwise it might lead to memory
corruption issues.
Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
SKBs that are allocated in the HTC layer do not have callbacks
registered and hence ended up not being freed, Fix this by freeing
them properly in the TX completion routine.
Reported-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com> Tested-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The length parameter should be sizeof(req->name) - 1 because there is no
guarantee that string provided by userspace will contain the trailing
'\0'.
Can be easily reproduced by manually setting req->name to 128 non-zero
bytes prior to ioctl(HIDPCONNADD) and checking the device name setup on
input subsystem:
When it goes to error through line 144, the memory allocated to *devname is
not freed, and the caller doesn't free it either in line 250. So we free the
memroy of *devname in function cifs_compose_mount_options() when it goes to
error.
Signed-off-by: Cong Ding <dinggnu@gmail.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This patch (as1644) fixes a race that occurs during startup in
uhci-hcd. If the IRQ line is shared with other devices, it's possible
for the handler routine to be called before the data structures are
fully initialized.
The problem is fixed by adding a check to the IRQ handler routine. If
the initialization hasn't finished yet, the routine will return
immediately.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Don Zickus <dzickus@redhat.com> Tested-by: "Huang, Adrian (ISS Linux TW)" <adrian.huang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If some other kernel subsystem has a module notifier, and adds a kprobe
to a ftrace mcount point (now that kprobes work on ftrace points),
when the ftrace notifier runs it will fail and disable ftrace, as well
as kprobes that are attached to ftrace points.
A kprobe was added to the init_once() function in the fat module on load.
But this happened before ftrace could have touched the code. As ftrace
didn't run yet, the kprobe system had no idea it was a ftrace point and
simply added a breakpoint to the code (0xcc in the cc:bb:d2:4b:e1).
Then when ftrace went to modify the location from a call to mcount/fentry
into a nop, it didn't see a call op, but instead it saw the breakpoint op
and not knowing what to do with it, ftrace shut itself down.
The solution is to simply give the ftrace module notifier the max priority.
This should have been done regardless, as the core code ftrace modification
also happens very early on in boot up. This makes the module modification
closer to core modification.
Link: http://lkml.kernel.org/r/20130107140333.593683061@goodmis.org Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reported-by: Frank Ch. Eigler <fche@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Subhash Jadavani reported this partial backtrace:
Now consider this call stack from MMC block driver (this is on the ARMv7
based board):
[<c001b50c>] (v7_dma_inv_range+0x30/0x48) from [<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c)
[<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c) from [<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c)
[<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c) from [<c0017ff8>] (dma_map_sg+0x3c/0x114)
This is caused by incrementing the struct page pointer, and running off
the end of the sparsemem page array. Fix this by incrementing by pfn
instead, and convert the pfn to a struct page.
Suggested-by: James Bottomley <JBottomley@Parallels.com> Tested-by: Subhash Jadavani <subhashj@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
acpi_processor_get_power_info() has to be called before
acpi_processor_setup_cpuidle_states() to have the latest
information available. This fixes the missing C-state information
after AC-->DC transition.
Signed-off-by: Thomas Schlichter <thomas.schlichter@web.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
(in acpi_processor_power_init) and never sets the per_cpu idle
device. So when acpi_processor_hotplug on CPU online notification
tries to reference said device it crashes:
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The 'intel_idle_probe' probes the CPU and sets the CPU notifier.
But if later on during the module initialization we fail (say
in cpuidle_register_driver), we stop loading, but we neglect
to unregister the CPU notifier. This means that during CPU
hotplug events the system will fail:
calling intel_idle_init+0x0/0x326 @ 1
intel_idle: MWAIT substates: 0x1120
intel_idle: v0.4 model 0x2A
intel_idle: lapic_timer_reliable_states 0xffffffff
intel_idle: intel_idle yielding to none
initcall intel_idle_init+0x0/0x326 returned -19 after 14 usecs
... some time later, offlining and onlining a CPU:
This patch fixes that by moving the CPU notifier registration
as the last item to be done by the module.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[bwh: Backported to 3.2: notifier is registered only if we do not have ARAT] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Guests can trigger MMIO exits using dcbf. Since we don't emulate cache
incoherent MMIO, just do nothing and move on.
Reported-by: Ben Collins <ben.c@servergy.com> Signed-off-by: Alexander Graf <agraf@suse.de> Tested-by: Ben Collins <ben.c@servergy.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Add support for the UART device present in Broadcom TruManage capable
NetXtreme chips (ie: 5761m 5762, and 5725).
This implementation has a hidden transmit FIFO, so running in single-byte
interrupt mode results in too many interrupts. The UART_CAP_HFIFO
capability was added to track this. It continues to reload the THR as long
as the THRE and TSRE bits are set in the LSR up to a specified limit (1024
is used here).
Signed-off-by: Stephen Hurd <shurd@broadcom.com> Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2:
- Adjust filenames
- Adjust context
- First available port type number is 22 not 24
- s/uart_8250_port/uart_port/
- Use serial_in() not serial_port_in()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
vt6656 has several headers that use the #pragma pack(1) directive to
enable structure packing, but never disable it. The layout of
structures defined in other headers can then depend on which order the
various headers are included in, breaking the One Definition Rule.
In practice this resulted in crashes on x86_64 until the order of header
inclusion was changed for some files in commit 11d404cb56ecd ('staging:
vt6656: fix headers and add cfg80211.'). But we need a proper fix that
won't be affected by future changes to the order of inclusion.
This removes the #pragma pack(1) directives and adds __packed to the
structure definitions for which packing appears to have been intended.
Reported-and-tested-by: Malcolm Priestley <tvboxspy@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2]
There has been an error on the xen_failsafe_callback path for failed
iret, which causes the stack pointer to be wrong when entering the
iret_exc error path. This can result in the kernel crashing.
In the classic kernel case, the relevant code looked a little like:
popl %eax # Error code from hypervisor
jz 5f
addl $16,%esp
jmp iret_exc # Hypervisor said iret fault
5: addl $16,%esp
# Hypervisor said segment selector fault
Here, there are two identical addls on either option of a branch which
appears to have been optimised by hoisting it above the jz, and
converting it to an lea, which leaves the flags register unaffected.
In the PVOPS case, the code looks like:
popl_cfi %eax # Error from the hypervisor
lea 16(%esp),%esp # Add $16 before choosing fault path
CFI_ADJUST_CFA_OFFSET -16
jz 5f
addl $16,%esp # Incorrectly adjust %esp again
jmp iret_exc
It is possible unprivileged userspace applications to cause this
behaviour, for example by loading an LDT code selector, then changing
the code selector to be not-present. At this point, there is a race
condition where it is possible for the hypervisor to return back to
userspace from an interrupt, fault on its own iret, and inject a
failsafe_callback into the kernel.
This bug has been present since the introduction of Xen PVOPS support
in commit 5ead97c84 (xen: Core Xen implementation), in 2.6.23.
Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We currently use a temporary 1MB section aligned to a 1MB boundary for
mapping the provided device tree until the final page table is created.
However, if the device tree happens to cross that 1MB boundary, the end
of it remains unmapped and the kernel crashes when it attempts to access
it. Given no restriction on the location of that DTB, it could end up
with only a few bytes mapped at the end of a section.
Solve this issue by mapping two consecutive sections.
Signed-off-by: Nicolas Pitre <nico@linaro.org> Tested-by: Sascha Hauer <s.hauer@pengutronix.de> Tested-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2:
- Adjust context
- The mapping is not conditional; drop the 'ne' suffixes] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Patrik Kluba reports that the preempt count becomes invalid due
to the preempt_enable() call being unbalanced with a
preempt_disable() call in the vfp assembly routines. This happens
because preempt_enable() and preempt_disable() update preempt
counts under PREEMPT_COUNT=y but the vfp assembly routines do so
under PREEMPT=y. In a configuration where PREEMPT=n and
DEBUG_ATOMIC_SLEEP=y, PREEMPT_COUNT=y and so the preempt_enable()
call in VFP_bounce() keeps subtracting from the preempt count
until it goes negative.
Fix this by always using PREEMPT_COUNT to decided when to update
preempt counts in the ARM assembly code.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reported-by: Patrik Kluba <pkluba@dension.com> Tested-by: Patrik Kluba <pkluba@dension.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Converting a 64 Bit TOD format value to nanoseconds means that the value
must be divided by 4.096. In order to achieve that we multiply with 125
and divide by 512.
When used within sched_clock() this triggers an overflow after appr.
417 days. Resulting in a sched_clock() return value that is much smaller
than previously and therefore may cause all sort of weird things in
subsystems that rely on a monotonic sched_clock() behaviour.
To fix this implement a tod_to_ns() helper function which converts TOD
values without overflow and call this function from both places that
open coded the conversion: sched_clock() and kvm_s390_handle_wait().
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In the slow path, we are forced to copy the relocations prior to
acquiring the struct mutex in order to handle pagefaults. We forgo
copying the new offsets back into the relocation entries in order to
prevent a recursive locking bug should we trigger a pagefault whilst
holding the mutex for the reservations of the execbuffer. Therefore, we
need to reset the presumed_offsets just in case the objects are rebound
back into their old locations after relocating for this exexbuffer - if
that were to happen we would assume the relocations were valid and leave
the actual pointers to the kernels dangling, instant hang.
drm/i915: Handle pagefaults in execbuffer user relocations
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=55984 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vetter@fwll.ch> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When shut down SPI port, it's possible that MRDY has been asserted and a SPI
timer was activated waiting for SRDY assert, in the case, it needs to delete
this timer.
Signed-off-by: Chen Jun <jun.d.chen@intel.com> Signed-off-by: channing <chao.bi@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Right now using pcie_aspm=force will not enable ASPM if the FADT indicates
ASPM is unsupported. However, the semantics of force should probably allow
for this, especially as they did before 3c076351c4 ("PCI: Rework ASPM
disable code")
This patch just skips the clearing of any ASPM setup that the firmware has
carried out on this bus if pcie_aspm=force is being used.
Reference: http://bugs.launchpad.net/bugs/962038 Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When we have an SHPC-capable bridge with a second SHPC-capable bridge
below it, pushing the upstream bridge's attention button causes a
deadlock.
The deadlock happens because we use the shpchp_wq workqueue to run
shpchp_pushbutton_thread(), which uses shpchp_disable_slot() to remove
devices below the upstream bridge. When we remove the downstream bridge,
we call shpc_remove(), the shpchp driver's .remove() method. That calls
flush_workqueue(shpchp_wq), which deadlocks because the
shpchp_pushbutton_thread() work item is still running.
This patch avoids the deadlock by creating a workqueue for every slot
and removing the single shared workqueue.
Use non-ordered workqueue for attention button events.
Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in shpchp as a result.
486b10b9f4 ("PCI: pciehp: Handle push button event asynchronously") made
the same change to pciehp. I split this out from a patch by Yijing Wang
<wangyijing@huawei.com> so we fix one thing at a time and to make the
shpchp history correspond more closely with the pciehp history.
The function aer_recover_queue() calls pci_get_domain_bus_and_slot(), which
requires that the caller decrement the reference count with pci_dev_put().
This patch adds the missing call to pci_dev_put().
Signed-off-by: Betty Dall <betty.dall@hp.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Shuah Khan <shuah.khan@hp.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Simple fix to add support for Crucible Technologies COMET Caller ID
USB decoder - a device containing FTDI USB/Serial converter chip,
handling 1200bps CallerID messages decoded from the phone line -
adding correct USB PID is sufficient.
Tested to apply cleanly and work flawlessly against 3.6.9, 3.7.0-rc8
and 3.8.0-rc3 on both amd64 and x86 arches.
Signed-off-by: Tomasz Mloduchowski <q@qdot.me> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When we have a hotplug-capable PCIe port with a second hotplug-capable
PCIe port below it, removing the device below the upstream port causes
a deadlock.
The deadlock happens because we use the pciehp_wq workqueue to run
pciehp_power_thread(), which uses pciehp_disable_slot() to remove devices
below the upstream port. When we remove the downstream PCIe port, we call
pciehp_remove(), the pciehp driver's .remove() method. That calls
flush_workqueue(pciehp_wq), which deadlocks because the
pciehp_power_thread() work item is still running.
This patch avoids the deadlock by creating a workqueue for every PCIe port
and removing the single shared workqueue.
Use non-ordered workqueue for attention button events.
Attention button events on each slot can be handled asynchronously. So
we should use non-ordered workqueue. This patch also removes ordered
workqueue in pciehp as a result.
In the current pciehp, pcied_cleanup() calls destroy_workqueue()
before calling pcie_port_service_unregister(). This causes kernel oops
because flush_workqueue() is called in the pcie_port_service_unregister()
code path after the workqueue was destroyed. So pcied_cleanup() must call
pcie_port_service_unregister() first before calling destroy_workqueue().
The current calculation in pfn_to_bitidx assumes that (pfn -
zone->zone_start_pfn) >> pageblock_order will return the same bit for
all pfn in a pageblock. If zone_start_pfn is not aligned to
pageblock_nr_pages, this may not always be correct.
Consider the following with pageblock order = 10, zone start 2MB:
This means that calling {get,set}_pageblock_migratetype on a single page
will not set the migratetype for the full block. Fix this by rounding
down zone_start_pfn when doing the bitidx calculation.
For our use case, the effects of this bug were mostly tied to the fact
that CMA allocations would either take a long time or fail to happen.
Depending on the driver using CMA, this could result in anything from
visual glitches to application failures.
Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Some touchscreens have buggy firmware which claims
remote wakeup to be enabled after a reset. They nevertheless
crash if the feature is cleared by the host.
Add a check for reset resume before checking for
an enabled remote wakeup feature. On compliant
devices the feature must be cleared after a reset anyway.
Signed-off-by: Oliver Neukum <oneukum@suse.de> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Ensure that the aux table is properly initialized, even when optional features
are missing. Without this, the FDPIC loader did not work. This was meant to
be included in commit d5ab780305bb6d60a7b5a74f18cf84eb6ad153b1.
Signed-off-by: Thomas Schwinge <thomas@codesourcery.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Clear the target role when no target is provided for
the node performing a PRLI.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Reviewed-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Acked by Robert Love <robert.w.love@intel.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When generating a PRLI response to an initiator, clear the
FCP_SPPF_RETRY bit in the response.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com> Reviewed-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Acked by Robert Love <robert.w.love@intel.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Those rn50 chip are often connected to console remoting hw and load
detection often fails with those. Just don't try to load detect and
report connect.
Signed-off-by: Jerome Glisse <jglisse@redhat.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use DIV_ROUND_UP to prevent truncation by integer division issue.
This ensures we return enough delay time.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[bwh: Backported to 3.2: delay is done by driver, not returned to the caller] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The ASC/ASCQ code for 'Logical Unit Communication failure' is
0x08/0x00; 0x80/0x00 is vendor specific.
Signed-off-by: Hannes Reinecke <hare@suse.de> Cc: Nicholas Bellinger <nab@risingtidesystems.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
[bwh: Backported to 3.2: add offset to buffer index] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If the rpc_task exits while holding the socket write lock before it has
allocated an rpc slot, then the usual mechanism for releasing the write
lock in xprt_release() is defeated.
The problem occurs if the call to xprt_lock_write() initially fails, so
that the rpc_task is put on the xprt->sending wait queue. If the task
exits after being assigned the lock by __xprt_lock_write_func, but
before it has retried the call to xprt_lock_and_alloc_slot(), then
it calls xprt_release() while holding the write lock, but will
immediately exit due to the test for task->tk_rqstp != NULL.
Reported-by: Chris Perl <chris.perl@gmail.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This patch fixes some code that implements a work-around to a hardware bug in
the ac97 controller on the pxa27x. A bug in the controller's warm reset
functionality requires that the mfp used by the controller as the AC97_nRESET
line be temporarily reconfigured as a generic output gpio (AF0) and manually
held high for the duration of the warm reset cycle. This is what was done in
the original code, but it was broken long ago by commit fb1bf8cd
([ARM] pxa: introduce processor specific pxa27x_assert_ac97reset())
which changed the mfp to a GPIO input instead of a high output.
The fix requires the ac97 controller to obtain the gpio via gpio_request_one(),
with arguments that configure the gpio as an output initially driven high.
Tested on a palm treo 680 machine. Reportedly, this broken code only prevents a
warm reset on hardware that lacks a pull-up on the line, which appears to be the
case for me.
Signed-off-by: Mike Dunn <mikedunn@newsguy.com> Signed-off-by: Igor Grinberg <grinberg@compulab.co.il> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
appears in the kernel log. Through trial-and-error (the pxa270 developer's
manual is mostly incoherent on the topic of ac97 reset), I got cold reset to
complete by setting the WARM_RST bit in the GCR register (and later noticed that
pxa3xx does this for cold reset as well). Also, a timeout loop is needed to
wait for the reset to complete.
Tested on a palm treo 680 machine.
Signed-off-by: Mike Dunn <mikedunn@newsguy.com> Acked-by: Igor Grinberg <grinberg@compulab.co.il> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Current code does integer division (min_vol = min_uV / 1000) before pass
min_vol to max8997_get_voltage_proper_val().
So it is possible min_vol is truncated to a smaller value.
For example, if the request min_uV is 800900 for ldo.
min_vol = 800900 / 1000 = 800 (mV)
Then max8997_get_voltage_proper_val returns 800 mV for this case which is lower
than the requested voltage.
Use uV rather than mV in voltage_map_desc to prevent truncation by integer
division.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
[bwh: Backported to 3.2:
- Adjust context
- voltage_map_desc also has an n_bits field] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Éric Piel reported a kernel oops in the "comedi_test" module. It was a
NULL pointer dereference within `waveform_ai_interrupt()` (actually a
timer function) that sometimes occurred when a running asynchronous
command is cancelled (either by the `COMEDI_CANCEL` ioctl or by closing
the device file).
This seems to be a race between the caller of `waveform_ai_cancel()`
which on return from that function goes and tears down the running
command, and the timer function which uses the command. In particular,
`async->cmd.chanlist` gets freed (and the pointer set to NULL) by
`do_become_nonbusy()` in "comedi_fops.c" but a previously scheduled
`waveform_ai_interrupt()` timer function will dereference that pointer
regardless, leading to the oops.
Fix it by replacing the `del_timer()` call in `waveform_ai_cancel()`
with `del_timer_sync()`.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reported-by: Éric Piel <piel@delmic.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The minimum period was set to 357 ns, while the divider for these boards is 50
ns. This prevented to output at maximum speed as ni_ao_cmdtest() would return
357 but would not accept it.
Not sure why it was set to 357 ns (this was done before the git history,
which starts 5 years ago). My guess is that it comes from reading the
specification stating a 2.8 MHz rate (~ 357 ns). The latest
specification states a 2.86 MHz rate (~ 350 ns), which makes a lot
more sense.
Tested on a pci-6251.
Signed-off-by: Éric Piel <piel@delmic.com> Acked-By: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: drop hunk for a board that's not listed] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The ISY IWL 1000 USB WLAN stick with USB ID 050d:11f1 is a clone of
the Belkin F7D1101 V1 device.
Reported-by: Thomas Hartmann <hartmann@ict.tuwien.ac.at> Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Cc: Thomas Hartmann <hartmann@ict.tuwien.ac.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
As along the error path we do not correct the user pin-count for the
failure, we may end up with userspace believing that it has a pinned
object at offset 0 (when interrupted by a signal for example).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ioat does DMA memory sync with DMA_TO_DEVICE direction on a buffer allocated
for DMA_FROM_DEVICE dma, resulting in the following warning from dma debug.
Fixed the dma_sync_single_for_device() call to use the correct direction.
wait_event_interruptible function returns -ERESTARTSYS if it's
interrupted by a signal. Driver should check the return value
and handle this case properly.
In mwifiex_wait_queue_complete() routine, as we are now checking
wait_event_interruptible return value, the condition check is not
required. Also, we have removed mwifiex_cancel_pending_ioctl()
call to avoid a chance of sending second command to FW by other path
as soon as we clear current command node. FW can not handle two
commands simultaneously.
Signed-off-by: Bing Zhao <bzhao@marvell.com> Signed-off-by: Amitkumar Karwar <akarwar@marvell.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Currently even if association is failed "iw link" shows some
information about connected BSS and "Tx timeout" error is seen in
dmesg log.
This patch fixes below issues in the code to handle assoc failure
case correctly.
1) "status" variable in mwifiex_wait_queue_complete() is not
correctly updated. Hence driver doesn't inform cfg80211 stack
about association failure.
2) During association network queues are stopped but carrier is
not cleared, which gives Tx timeout error in failure case
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com> Signed-off-by: Bing Zhao <bzhao@marvell.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The USB core hub thread (khubd) is designed with external USB hubs in
mind. It expects that if a port status change bit is set, the hub will
continue to send a notification through the hub status data transfer.
Basically, it expects hub notifications to be level-triggered.
The xHCI host controller is designed to be edge-triggered on the logical
'OR' of all the port status change bits. When all port status change
bits are clear, and a new change bit is set, the xHC will generate a
Port Status Change Event. If another change bit is set in the same port
status register before the first bit is cleared, it will not send
another event.
This means that the hub code may lose port status changes because of
race conditions between clearing change bits. The user sees this as a
"dead port" that doesn't react to device connects.
The fix is to turn on port polling whenever a new change bit is set.
Once the USB core issues a hub status request that shows that no change
bits are set in any USB ports, turn off port polling.
We can't allow the USB core to poll the roothub for port events during
host suspend because if the PCI host is in D3cold, the port registers
will be all f's. Instead, stop the port polling timer, and
unconditionally restart it when the host resumes. If there are no port
change bits set after the resume, the first call to hub_status_data will
disable polling.
This patch should be backported to stable kernels with the first xHCI
support, 2.6.31 and newer, that include the commit 0f2a79300a1471cf92ab43af165ea13555c8b0a5 "USB: xhci: Root hub support."
There will be merge conflicts because the check for HC_STATE_SUSPENDED
was moved into xhci_suspend in 3.8.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
An empty port can transition to either Inactive or Compliance Mode if a
newly connected USB 3.0 device fails to link train. In that case, we
issue a warm reset. Some devices, such as John's Roseweil eusb3
enclosure, slip back into Compliance Mode after the warm reset.
The current warm reset code does not check for device connect status on
warm reset completion, and it incorrectly reports the warm reset
succeeded. This causes the USB core to attempt to send a Set Address
control transfer to a port in Compliance Mode, which will always fail.
Make hub_port_wait_reset check the current connect status and link state
after the warm reset completes. Return a failure status if the device
is disconnected or the link state is Compliance Mode or SS.Inactive.
Make hub_events disable the port if warm reset fails. This will disable
the port, and then bring it back into the RxDetect state. Make the USB
core ignore the connect change until the device reconnects.
Note that this patch does NOT handle connected devices slipping into the
Inactive state very well. This is a concern, because devices can go
into the Inactive state on U1/U2 exit failure. However, the fix for
that case is too large for stable, so it will be submitted in a separate
patch.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: John Covici <covici@ccs.covici.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The port reset code bails out early if the current connect status is
cleared (device disconnected). If we're issuing a hot reset, it may
also look at the link state before the reset is finished.
Section 10.14.2.6 of the USB 3.0 spec says that when a port enters the
Error state or Resetting state, the port connection bit retains the
value from the previous state. Therefore we can't trust it until the
reset finishes. Also, the xHCI spec section 4.19.1.2.5 says software
shall ignore the link state while the port is resetting, as it can be in
an unknown state.
The port state during reset is also unknown for USB 2.0 hubs. The hub
sends a reset signal by driving the bus into an SE0 state. This
overwhelms the "connect" signal from the device, so the port can't tell
whether anything is connected or not.
Fix the port reset code to ignore the port link state and current
connect bit until the reset finishes, and USB_PORT_STAT_RESET is
cleared.
Remove the check for USB_PORT_STAT_C_BH_RESET in the warm reset case,
because it's redundant. When the warm reset finishes, the port reset
bit will be cleared at the same time USB_PORT_STAT_C_BH_RESET is set.
Remove the now-redundant check for a cleared USB_PORT_STAT_RESET bit
in the code to deal with the finished reset.
This patch should be backported to all stable kernels.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>