linux-stable.git/drivers/misc, branch v4.14.52

vmw_balloon: fixing double free when batching mode is off

2018-06-16T07:45:16+00:00

commit b23220fe054e92f616b82450fae8cd3ab176cc60 upstream.

The balloon.page field is used for two different purposes if batching is
on or off. If batching is on, the field point to the page which is used
to communicate with with the hypervisor. If it is off, balloon.page
points to the page that is about to be (un)locked.

Unfortunately, this dual-purpose of the field introduced a bug: when the
balloon is popped (e.g., when the machine is reset or the balloon driver
is explicitly removed), the balloon driver frees, unconditionally, the
page that is held in balloon.page.  As a result, if batching is
disabled, this leads to double freeing the last page that is sent to the
hypervisor.

The following error occurs during rmmod when kernel checkers are on, and
the balloon is not empty:

[   42.307653] ------------[ cut here ]------------
[   42.307657] Kernel BUG at ffffffffba1e4b28 [verbose debug info unavailable]
[   42.307720] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
[   42.312512] Modules linked in: vmw_vsock_vmci_transport vsock ppdev joydev vmw_balloon(-) input_leds serio_raw vmw_vmci parport_pc shpchp parport i2c_piix4 nfit mac_hid autofs4 vmwgfx drm_kms_helper hid_generic syscopyarea sysfillrect usbhid sysimgblt fb_sys_fops hid ttm mptspi scsi_transport_spi ahci mptscsih drm psmouse vmxnet3 libahci mptbase pata_acpi
[   42.312766] CPU: 10 PID: 1527 Comm: rmmod Not tainted 4.12.0+ #5
[   42.312803] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/30/2016
[   42.313042] task: ffff9bf9680f8000 task.stack: ffffbfefc1638000
[   42.313290] RIP: 0010:__free_pages+0x38/0x40
[   42.313510] RSP: 0018:ffffbfefc163be98 EFLAGS: 00010246
[   42.313731] RAX: 000000000000003e RBX: ffffffffc02b9720 RCX: 0000000000000006
[   42.313972] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9bf97e08e0a0
[   42.314201] RBP: ffffbfefc163be98 R08: 0000000000000000 R09: 0000000000000000
[   42.314435] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffc02b97e4
[   42.314505] R13: ffffffffc02b9748 R14: ffffffffc02b9728 R15: 0000000000000200
[   42.314550] FS:  00007f3af5fec700(0000) GS:ffff9bf97e080000(0000) knlGS:0000000000000000
[   42.314599] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   42.314635] CR2: 00007f44f6f4ab24 CR3: 00000003a7d12000 CR4: 00000000000006e0
[   42.314864] Call Trace:
[   42.315774]  vmballoon_pop+0x102/0x130 [vmw_balloon]
[   42.315816]  vmballoon_exit+0x42/0xd64 [vmw_balloon]
[   42.315853]  SyS_delete_module+0x1e2/0x250
[   42.315891]  entry_SYSCALL_64_fastpath+0x23/0xc2
[   42.315924] RIP: 0033:0x7f3af5b0e8e7
[   42.315949] RSP: 002b:00007fffe6ce0148 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
[   42.315996] RAX: ffffffffffffffda RBX: 000055be676401e0 RCX: 00007f3af5b0e8e7
[   42.316951] RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055be67640248
[   42.317887] RBP: 0000000000000003 R08: 0000000000000000 R09: 1999999999999999
[   42.318845] R10: 0000000000000883 R11: 0000000000000206 R12: 00007fffe6cdf130
[   42.319755] R13: 0000000000000000 R14: 0000000000000000 R15: 000055be676401e0
[   42.320606] Code: c0 74 1c f0 ff 4f 1c 74 02 5d c3 85 f6 74 07 e8 0f d8 ff ff 5d c3 31 f6 e8 c6 fb ff ff 5d c3 48 c7 c6 c8 0f c5 ba e8 58 be 02 00 <0f> 0b 66 0f 1f 44 00 00 66 66 66 66 90 48 85 ff 75 01 c3 55 48
[   42.323462] RIP: __free_pages+0x38/0x40 RSP: ffffbfefc163be98
[   42.325735] ---[ end trace 872e008e33f81508 ]---

To solve the bug, we eliminate the dual purpose of balloon.page.

Fixes: f220a80f0c2e ("VMware balloon: add batching to the vmw_balloon.")
Cc: stable@vger.kernel.org
Reported-by: Oleksandr Natalenko 
Signed-off-by: Gil Kupfer 
Signed-off-by: Nadav Amit 
Reviewed-by: Xavier Deguillard 
Tested-by: Oleksandr Natalenko 
Signed-off-by: Greg Kroah-Hartman

cxl: Check if PSL data-cache is available before issue flush request

2018-05-30T05:52:33+00:00

[ Upstream commit 94322ed8e857e3b2a33cf75118051af9baaa110f ]

PSL9D doesn't have a data-cache that needs to be flushed before
resetting the card. However when cxl tries to flush data-cache on such
a card, it times-out as PSL_Control register never indicates flush
operation complete due to missing data-cache. This is usually
indicated in the kernel logs with this message:

"WARNING: cache flush timed out"

To fix this the patch checks PSL_Debug register CDC-Field(BIT:27)
which indicates the absence of a data-cache and sets a flag
'no_data_cache' in 'struct cxl_native' to indicate this. When
cxl_data_cache_flush() is called it checks the flag and if set bails
out early without requesting a data-cache flush operation to the PSL.

Signed-off-by: Vaibhav Jain 
Acked-by: Andrew Donnellan 
Acked-by: Frederic Barrat 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

cxl: Fix possible deadlock when processing page faults from cxllib

2018-04-24T07:36:32+00:00

commit ad7b4e8022b9864c075fe71e1328b1d25cad82f6 upstream.

cxllib_handle_fault() is called by an external driver when it needs to
have the host resolve page faults for a buffer. The buffer can cover
several pages and VMAs. The function iterates over all the pages used
by the buffer, based on the page size of the VMA.

To ensure some stability while processing the faults, the thread T1
grabs the mm->mmap_sem semaphore with read access (R1). However, when
processing a page fault for a single page, one of the underlying
functions, copro_handle_mm_fault(), also grabs the same semaphore with
read access (R2). So the thread T1 takes the semaphore twice.

If another thread T2 tries to access the semaphore in write mode W1
(say, because it wants to allocate memory and calls 'brk'), then that
thread T2 will have to wait because there's a reader (R1). If the
thread T1 is processing a new page at that time, it won't get an
automatic grant at R2, because there's now a writer thread
waiting (T2). And we have a deadlock.

The timeline is:
1. thread T1 owns the semaphore with read access R1
2. thread T2 requests write access W1 and waits
3. thread T1 requests read access R2 and waits

The fix is for the thread T1 to release the semaphore R1 once it got
the information it needs from the current VMA. The address space/VMAs
could evolve while T1 iterates over the full buffer, but in the
unlikely case where T1 misses a page, the external driver will raise a
new page fault when retrying the memory access.

Fixes: 3ced8d730063 ("cxl: Export library to support IBM XSL")
Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: Frederic Barrat 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

mei: remove dev_err message on an unsupported ioctl

2018-04-08T12:26:31+00:00

commit bb0829a741792b56c908d7745bc0b2b540293bcc upstream.

Currently the driver spams the kernel log on unsupported ioctls which is
unnecessary as the ioctl returns -ENOIOCTLCMD to indicate this anyway.
I suspect this was originally for debugging purposes but it really is not
required so remove it.

Signed-off-by: Colin Ian King 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

mei: me: add cannon point device ids for 4th device

2018-02-25T10:08:04+00:00

commit 2a4ac172c2f257d28c47b90c9e381bec31edcc44 upstream.

Add cannon point device ids for 4th (itouch) device.

Cc:  4.14+
Signed-off-by: Tomas Winkler 
Signed-off-by: Greg Kroah-Hartman

mei: me: add cannon point device ids

2018-02-25T10:08:04+00:00

commit f8f4aa68a8ae98ed79c8fee3488c38a2f5d2de8c upstream.

Add CNP LP and CNP H device ids for cannon lake
and coffee lake platforms.

Cc:  4.14+
Signed-off-by: Alexander Usyskin 
Signed-off-by: Tomas Winkler 
Signed-off-by: Greg Kroah-Hartman

kmemcheck: remove annotations

2018-02-22T14:42:23+00:00

commit 4950276672fce5c241857540f8561c440663673d upstream.

Patch series "kmemcheck: kill kmemcheck", v2.

As discussed at LSF/MM, kill kmemcheck.

KASan is a replacement that is able to work without the limitation of
kmemcheck (single CPU, slow).  KASan is already upstream.

We are also not aware of any users of kmemcheck (or users who don't
consider KASan as a suitable replacement).

The only objection was that since KASAN wasn't supported by all GCC
versions provided by distros at that time we should hold off for 2
years, and try again.

Now that 2 years have passed, and all distros provide gcc that supports
KASAN, kill kmemcheck again for the very same reasons.

This patch (of 4):

Remove kmemcheck annotations, and calls to kmemcheck from the kernel.

[alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs]
  Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com
Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com
Signed-off-by: Sasha Levin 
Cc: Alexander Potapenko 
Cc: Eric W. Biederman 
Cc: Michal Hocko 
Cc: Pekka Enberg 
Cc: Steven Rostedt 
Cc: Tim Hansen 
Cc: Vegard Nossum 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mei: me: allow runtime pm for platform with D0i3

2018-02-03T16:39:22+00:00

commit cc365dcf0e56271bedf3de95f88922abe248e951 upstream.

>From the pci power documentation:
"The driver itself should not call pm_runtime_allow(), though. Instead,
it should let user space or some platform-specific code do that (user space
can do it via sysfs as stated above)..."

However, the S0ix residency cannot be reached without MEI device getting
into low power state. Hence, for mei devices that support D0i3, it's better
to make runtime power management mandatory and not rely on the system
integration such as udev rules.
This policy cannot be applied globally as some older platforms
were found to have broken power management.

Cc: Rafael J. Wysocki 
Signed-off-by: Tomas Winkler 
Reviewed-by: Alexander Usyskin 
Signed-off-by: Greg Kroah-Hartman

drivers/misc/intel/pti: Rename the header file to free up the namespace

2017-12-25T13:26:20+00:00

commit 1784f9144b143a1e8b19fe94083b040aa559182b upstream.

We'd like to use the 'PTI' acronym for 'Page Table Isolation' - free up the
namespace by renaming the  driver header to .

(Also standardize the header guard name while at it.)

Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: J Freyensee 
Cc: Greg Kroah-Hartman 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

x86/virt: Add enum for hypervisors to replace x86_hyper

2017-12-25T13:26:20+00:00

commit 03b2a320b19f1424e9ac9c21696be9c60b6d0d93 upstream.

The x86_hyper pointer is only used for checking whether a virtual
device is supporting the hypervisor the system is running on.

Use an enum for that purpose instead and drop the x86_hyper pointer.

Signed-off-by: Juergen Gross 
Acked-by: Thomas Gleixner 
Acked-by: Xavier Deguillard 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: akataria@vmware.com
Cc: arnd@arndb.de
Cc: boris.ostrovsky@oracle.com
Cc: devel@linuxdriverproject.org
Cc: dmitry.torokhov@gmail.com
Cc: gregkh@linuxfoundation.org
Cc: haiyangz@microsoft.com
Cc: kvm@vger.kernel.org
Cc: kys@microsoft.com
Cc: linux-graphics-maintainer@vmware.com
Cc: linux-input@vger.kernel.org
Cc: moltmann@vmware.com
Cc: pbonzini@redhat.com
Cc: pv-drivers@vmware.com
Cc: rkrcmar@redhat.com
Cc: sthemmin@microsoft.com
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20171109132739.23465-3-jgross@suse.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman