[ Upstream commit d424986f1d ]
Set CONFIG_GENERIC_CPU_VULNERABILITIES and provide the two functions
cpu_show_spectre_v1 and cpu_show_spectre_v2 to report the spectre
mitigations.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit bc03559971 ]
Add a boot message if either of the spectre defenses is active.
The message is
"Spectre V2 mitigation: execute trampolines."
or "Spectre V2 mitigation: limited branch prediction."
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6e179d6412 ]
Automatically decide between nobp vs. expolines if the spectre_v2=auto
kernel parameter is specified or CONFIG_EXPOLINE_AUTO=y is set.
The decision made at boot time due to CONFIG_EXPOLINE_AUTO=y being set
can be overruled with the nobp, nospec and spectre_v2 kernel parameters.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b2e2f43a01 ]
Keep the code for the nobp parameter handling with the code for
expolines. Both are related to the spectre v2 mitigation.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d3f468963c ]
when a system call is interrupted we might call the critical section
cleanup handler that re-does some of the operations. When we are between
.Lsysc_vtime and .Lsysc_do_svc we might also redo the saving of the
problem state registers r0-r7:
.Lcleanup_system_call:
[...]
0: # update accounting time stamp
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
# set up saved register r11
lg %r15,__LC_KERNEL_STACK
la %r9,STACK_FRAME_OVERHEAD(%r15)
stg %r9,24(%r11) # r11 pt_regs pointer
# fill pt_regs
mvc __PT_R8(64,%r9),__LC_SAVE_AREA_SYNC
---> stmg %r0,%r7,__PT_R0(%r9)
The problem is now, that we might have already zeroed out r0.
The fix is to move the zeroing of r0 after sysc_do_svc.
Reported-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Fixes: 7041d28115 ("s390: scrub registers on kernel entry and KVM exit")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d5feec04fe ]
The system call path can be interrupted before the switch back to the
standard branch prediction with BPENTER has been done. The critical
section cleanup code skips forward to .Lsysc_do_svc and bypasses the
BPENTER. In this case the kernel and all subsequent code will run with
the limited branch prediction.
Fixes: eacf67eb9b32 ("s390: run user space and KVM guests with modified branch prediction")
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f315104ad8 ]
If the guest runs with bp isolation when doing a SIE instruction,
we must also run the nested guest with bp isolation when emulating
that SIE instruction.
This is done by activating BPBC in the lpar, which acts as an override
for lower level guests.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f19fbd5ed6 ]
Add CONFIG_EXPOLINE to enable the use of the new -mindirect-branch= and
-mfunction_return= compiler options to create a kernel fortified against
the specte v2 attack.
With CONFIG_EXPOLINE=y all indirect branches will be issued with an
execute type instruction. For z10 or newer the EXRL instruction will
be used, for older machines the EX instruction. The typical indirect
call
basr %r14,%r1
is replaced with a PC relative call to a new thunk
brasl %r14,__s390x_indirect_jump_r1
The thunk contains the EXRL/EX instruction to the indirect branch
__s390x_indirect_jump_r1:
exrl 0,0f
j .
0: br %r1
The detour via the execute type instruction has a performance impact.
To get rid of the detour the new kernel parameter "nospectre_v2" and
"spectre_v2=[on,off,auto]" can be used. If the parameter is specified
the kernel and module code will be patched at runtime.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6b73044b2b ]
Define TIF_ISOLATE_BP and TIF_ISOLATE_BP_GUEST and add the necessary
plumbing in entry.S to be able to run user space and KVM guests with
limited branch prediction.
To switch a user space process to limited branch prediction the
s390_isolate_bp() function has to be call, and to run a vCPU of a KVM
guest associated with the current task with limited branch prediction
call s390_isolate_bp_guest().
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d768bd892f ]
Add the PPA instruction to the system entry and exit path to switch
the kernel to a different branch prediction behaviour. The instructions
are added via CPU alternatives and can be disabled with the "nospec"
or the "nobp=0" kernel parameter. If the default behaviour selected
with CONFIG_KERNEL_NOBP is set to "n" then the "nobp=1" parameter can be
used to enable the changed kernel branch prediction.
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cf14899846 ]
To be able to switch off specific CPU alternatives with kernel parameters
make a copy of the facility bit mask provided by STFLE and use the copy
for the decision to apply an alternative.
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e2dd833389 ]
Add an optimized version of the array_index_mask_nospec function for
s390 based on a compare and a subtract with borrow.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7041d28115 ]
Clear all user space registers on entry to the kernel and all KVM guest
registers on KVM guest exit if the register does not contain either a
parameter or a result value.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 35b3fde620 ]
The new firmware interfaces for branch prediction behaviour changes
are transparently available for the guest. Nevertheless, there is
new state attached that should be migrated and properly resetted.
Provide a mechanism for handling reset, migration and VSIE.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
[Changed capability number to 152. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 049a2c2d48 ]
Remove the CPU_ALTERNATIVES config option and enable the code
unconditionally. The config option was only added to avoid a conflict
with the named saved segment support. Since that code is gone there is
no reason to keep the CPU_ALTERNATIVES config option.
Just enable it unconditionally to also reduce the number of config
options and make it less likely that something breaks.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 686140a1a9 ]
Implement CPU alternatives, which allows to optionally patch newer
instructions at runtime, based on CPU facilities availability.
A new kernel boot parameter "noaltinstr" disables patching.
Current implementation is derived from x86 alternatives. Although
ideal instructions padding (when altinstr is longer then oldinstr)
is added at compile time, and no oldinstr nops optimization has to be
done at runtime. Also couple of compile time sanity checks are done:
1. oldinstr and altinstr must be <= 254 bytes long,
2. oldinstr and altinstr must not have an odd length.
alternative(oldinstr, altinstr, facility);
alternative_2(oldinstr, altinstr1, facility1, altinstr2, facility2);
Both compile time and runtime padding consists of either 6/4/2 bytes nop
or a jump (brcl) + 2 bytes nop filler if padding is longer then 6 bytes.
.altinstructions and .altinstr_replacement sections are part of
__init_begin : __init_end region and are freed after initialization.
Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 821cdad5c4 upstream.
Sporadic reset issues have been observed with an Intel 750 NVMe drive while
assigning the physical function to the guest machine. The sequence of
events observed is as follows:
- perform a Function Level Reset (FLR)
- sleep up to 1000ms total
- read ~0 from PCI_COMMAND (CRS completion for config read)
- warn that the device didn't return from FLR
- touch the device before it's ready
- device drops config writes when we restore register settings (there's
no mechanism for software to learn about CRS completions for writes)
- incomplete register restore leaves device in inconsistent state
- device probe fails because device is in inconsistent state
After reset, an endpoint may respond to config requests with Configuration
Request Retry Status (CRS) to indicate that it is not ready to accept new
requests. See PCIe r3.1, sec 2.3.1 and 6.6.2.
Increase the timeout value from 1 second to 60 seconds to cover the period
where device responds with CRS and also report polling progress.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
[bhelgaas: include the mandatory 100ms in the delays we print]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit f5a26acf01
Mike writes:
It seems that commit f5a26acf01 ("pinctrl: intel: Initialize GPIO
properly when used through irqchip") can cause problems on some Skylake
systems with Sunrisepoint PCH-H. Namely on certain systems it may turn
the backlight PWM pin from native mode to GPIO which makes the screen
blank during boot.
There is more information here:
https://bugzilla.redhat.com/show_bug.cgi?id=1543769
The actual reason is that GPIO numbering used in BIOS is using "Windows"
numbers meaning that they don't match the hardware 1:1 and because of
this a wrong pin (backlight PWM) is picked and switched to GPIO mode.
There is a proper fix for this but since it has quite many dependencies
on commits that cannot be considered stable material, I suggest we
revert commit f5a26acf01 from stable trees 4.9, 4.14 and 4.15 to
prevent the backlight issue.
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Fixes: f5a26acf01 ("pinctrl: intel: Initialize GPIO properly when used through irqchip")
Cc: Daniel Drake <drake@endlessm.com>
Cc: Chris Chiu <chiu@endlessm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 90841047a0 upstream.
This linksys dongle by default comes up in cdc_ether mode.
This patch allows r8152 to claim the device:
Bus 002 Device 002: ID 13b1:0041 Linksys
Signed-off-by: Grant Grundler <grundler@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
[krzk: Rebase on v4.4]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8cfd36a0b5 upstream.
When destroying a net namespace, all hwsim interfaces, which are not
created in default namespace are deleted. But the async deletion of the
interfaces could last longer than the actual destruction of the
namespace, which results to an use after free bug. Therefore use
synchronous deletion in this case.
Fixes: 100cb9ff40 ("mac80211_hwsim: Allow managing radios from non-initial namespaces")
Reported-by: syzbot+70ce058e01259de7bb1d@syzkaller.appspotmail.com
Signed-off-by: Benjamin Beichler <benjamin.beichler@uni-rostock.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5e1df40f40 upstream.
Currently we see sporadic timeouts during CDCLK changing both on BXT and
GLK as reported by the Bugzilla: ticket. It's easy to reproduce this by
changing the frequency in a tight loop after blanking the display. The
upper bound for the completion time is 800us based on my tests, so
increase it from the current 500us to 2ms; with that I couldn't trigger
the problem either on BXT or GLK.
Note that timeouts happened during both the change notification and the
voltage level setting PCODE request. (For the latter one BSpec doesn't
require us to wait for completion before further HW programming.)
This issue is similar to
commit 2c7d0602c8 ("drm/i915/gen9: Fix PCODE polling during CDCLK
change notification")
but there the PCODE request does complete (as shown by the mbox
busy flag), only the reply we get from PCODE indicates a failure.
So there we keep resending the request until a success reply, here we
just have to increase the timeout for the one PCODE request we send.
v2:
- s/snb_pcode_request/sandybridge_pcode_write_timeout/ (Ville)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v4.9
Acked-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103326
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180130142939.17983-1-imre.deak@intel.com
(cherry picked from commit e76019a819)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
(Rebased for v4.9 stable tree due to upstream intel_cdclk.c, cdclk_state and pcu_lock change)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dbfcef6b0f upstream.
Below is the synchronization issue between unmount and kjournald2
contexts, which results into use after free issue in kjournald2().
Fix this issue by using journal->j_state_lock to synchronize the
wait_event() done in journal_kill_thread() and the wake_up() done
in kjournald2().
TASK 1:
umount cmd:
|--jbd2_journal_destroy() {
|--journal_kill_thread() {
write_lock(&journal->j_state_lock);
journal->j_flags |= JBD2_UNMOUNT;
...
write_unlock(&journal->j_state_lock);
wake_up(&journal->j_wait_commit); TASK 2 wakes up here:
kjournald2() {
...
checks JBD2_UNMOUNT flag and calls goto end-loop;
...
end_loop:
write_unlock(&journal->j_state_lock);
journal->j_task = NULL; --> If this thread gets
pre-empted here, then TASK 1 wait_event will
exit even before this thread is completely
done.
wait_event(journal->j_wait_done_commit, journal->j_task == NULL);
...
write_lock(&journal->j_state_lock);
write_unlock(&journal->j_state_lock);
}
|--kfree(journal);
}
}
wake_up(&journal->j_wait_done_commit); --> this step
now results into use after free issue.
}
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a34d0a0da1 upstream.
In an RFC patch, Sven Eckelmann and Simon Wunderlich reported:
"QCA 802.11n chips (especially AR9330/AR9340) sometimes end up in a
state in which a read of AR_CFG always returns 0xdeadbeef.
This should not happen when when the power_mode of the device is
ATH9K_PM_AWAKE."
Include the check for the default register state in the existing MAC
hang check.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Cc: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d08876f524 upstream.
We pass an int pointer to stk_camera_read_reg() but only write to the
highest byte. It's a bug on big endian systems and generally a nasty
thing to do and doesn't match the write function either.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Cc: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 94e46a4f2d upstream.
This fixes an oops on unbind / module unload (on the musb omap2430
platform).
musb_remove function now calls musb_platform_exit before disabling
runtime pm.
Signed-off-by: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit df6b074dbe upstream.
Without pm_runtime_{get,put}_sync calls in place, reading
vbus status via /sys causes the following error:
Unhandled fault: external abort on non-linefetch (0x1028) at 0xfa0ab060
pgd = b333e822
[fa0ab060] *pgd=48011452(bad)
[<c05261b0>] (musb_default_readb) from [<c0525bd0>] (musb_vbus_show+0x58/0xe4)
[<c0525bd0>] (musb_vbus_show) from [<c04c0148>] (dev_attr_show+0x20/0x44)
[<c04c0148>] (dev_attr_show) from [<c0259f74>] (sysfs_kf_seq_show+0x80/0xdc)
[<c0259f74>] (sysfs_kf_seq_show) from [<c0210bac>] (seq_read+0x250/0x448)
[<c0210bac>] (seq_read) from [<c01edb40>] (__vfs_read+0x1c/0x118)
[<c01edb40>] (__vfs_read) from [<c01edccc>] (vfs_read+0x90/0x144)
[<c01edccc>] (vfs_read) from [<c01ee1d0>] (SyS_read+0x3c/0x74)
[<c01ee1d0>] (SyS_read) from [<c0106fe0>] (ret_fast_syscall+0x0/0x54)
Solution was suggested by Tony Lindgren <tony@atomide.com>.
Signed-off-by: Merlijn Wajer <merlijn@wizzup.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 17539f2f4f upstream.
On dm3730 there are enumeration problems after resume.
Investigation led to the cause that the MUSB_POWER_SOFTCONN
bit is not set. If it was set before suspend (because it
was enabled via musb_pullup()), it is set in
musb_restore_context() so the pullup is enabled. But then
musb_start() is called which overwrites MUSB_POWER and
therefore disables MUSB_POWER_SOFTCONN, so no pullup is
enabled and the device is not enumerated.
So let's do a subset of what musb_start() does
in the same way as musb_suspend() does it. Platform-specific
stuff it still called as there might be some phy-related stuff
which needs to be enabled.
Also interrupts are enabled, as it was the original idea
of calling musb_start() in musb_resume() according to
Commit 6fc6f4b87c ("usb: musb: Disable interrupts on suspend,
enable them on resume")
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f7f6d915a1 upstream.
On some systems, the BIOS expects certain SMBus register values to
match the hardware defaults. Restore these configuration registers at
shutdown time to avoid confusing the BIOS. This avoids hard-locking
such systems upon reboot.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a086bb8317 upstream.
Saving the original value of register SMBSLVCMD in
i801_enable_host_notify() doesn't work, because this function is
called not only at probe time but also at resume time. Do it in
i801_probe() instead, so that the saved value is not overwritten at
resume time.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 22e94bd677 ("i2c: i801: store and restore the SLVCMD register at load and unload")
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Tested-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7eb2c4dd54 upstream.
LSPCON adapters in low-power state may ignore the first I2C write during
TMDS output buffer enabling, resulting in a blank screen even with an
otherwise enabled pipe. Fix this by reading back and validating the
written value a few times.
The problem was noticed on GLK machines with an onboard LSPCON adapter
after entering/exiting DC5 power state. Doing an I2C read of the adapter
ID as the first transaction - instead of the I2C write to enable the
TMDS buffers - returns the correct value. Based on this we assume that
the transaction itself is sent properly, it's only the adapter that is
not ready for some reason to accept this first write after waking from
low-power state. In my case the second I2C write attempt always
succeeded.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105854
Cc: Clinton Taylor <clinton.a.taylor@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180416155309.11100-1-imre.deak@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d3878e164d upstream.
The TSC calibration code uses HPET as reference. The conversion normalizes
the delta of two HPET timestamps:
hpetref = ((tshpet1 - tshpet2) * HPET_PERIOD) / 1e6
and then divides the normalized delta of the corresponding TSC timestamps
by the result to calulate the TSC frequency.
tscfreq = ((tstsc1 - tstsc2 ) * 1e6) / hpetref
This uses do_div() which takes an u32 as the divisor, which worked so far
because the HPET frequency was low enough that 'hpetref' never exceeded
32bit.
On Skylake machines the HPET frequency increased so 'hpetref' can exceed
32bit. do_div() truncates the divisor, which causes the calibration to
fail.
Use div64_u64() to avoid the problem.
[ tglx: Fixes whitespace mangled patch and rewrote changelog ]
Signed-off-by: Xiaoming Gao <newtongao@tencent.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: peterz@infradead.org
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/38894564-4fc9-b8ec-353f-de702839e44e@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1d0cffa674 upstream.
RHBZ: 1453123
Since at least the 3.10 kernel and likely a lot earlier we have
not been able to create unix domain sockets in a cifs share
when mounted using the SFU mount option (except when mounted
with the cifs unix extensions to Samba e.g.)
Trying to create a socket, for example using the af_unix command from
xfstests will cause :
BUG: unable to handle kernel NULL pointer dereference at 00000000
00000040
Since no one uses or depends on being able to create unix domains sockets
on a cifs share the easiest fix to stop this vulnerability is to simply
not allow creation of any other special files than char or block devices
when sfu is used.
Added update to Ronnie's patch to handle a tcon link leak, and
to address a buf leak noticed by Gustavo and Colin.
Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
CC: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2e898e4c0a upstream.
lock_page_memcg()/unlock_page_memcg() use spin_lock_irqsave/restore() if
the page's memcg is undergoing move accounting, which occurs when a
process leaves its memcg for a new one that has
memory.move_charge_at_immigrate set.
unlocked_inode_to_wb_begin,end() use spin_lock_irq/spin_unlock_irq() if
the given inode is switching writeback domains. Switches occur when
enough writes are issued from a new domain.
This existing pattern is thus suspicious:
lock_page_memcg(page);
unlocked_inode_to_wb_begin(inode, &locked);
...
unlocked_inode_to_wb_end(inode, locked);
unlock_page_memcg(page);
If both inode switch and process memcg migration are both in-flight then
unlocked_inode_to_wb_end() will unconditionally enable interrupts while
still holding the lock_page_memcg() irq spinlock. This suggests the
possibility of deadlock if an interrupt occurs before unlock_page_memcg().
truncate
__cancel_dirty_page
lock_page_memcg
unlocked_inode_to_wb_begin
unlocked_inode_to_wb_end
<interrupts mistakenly enabled>
<interrupt>
end_page_writeback
test_clear_page_writeback
lock_page_memcg
<deadlock>
unlock_page_memcg
Due to configuration limitations this deadlock is not currently possible
because we don't mix cgroup writeback (a cgroupv2 feature) and
memory.move_charge_at_immigrate (a cgroupv1 feature).
If the kernel is hacked to always claim inode switching and memcg
moving_account, then this script triggers lockup in less than a minute:
cd /mnt/cgroup/memory
mkdir a b
echo 1 > a/memory.move_charge_at_immigrate
echo 1 > b/memory.move_charge_at_immigrate
(
echo $BASHPID > a/cgroup.procs
while true; do
dd if=/dev/zero of=/mnt/big bs=1M count=256
done
) &
while true; do
sync
done &
sleep 1h &
SLEEP=$!
while true; do
echo $SLEEP > a/cgroup.procs
echo $SLEEP > b/cgroup.procs
done
The deadlock does not seem possible, so it's debatable if there's any
reason to modify the kernel. I suggest we should to prevent future
surprises. And Wang Long said "this deadlock occurs three times in our
environment", so there's more reason to apply this, even to stable.
Stable 4.4 has minor conflicts applying this patch. For a clean 4.4 patch
see "[PATCH for-4.4] writeback: safer lock nesting"
https://lkml.org/lkml/2018/4/11/146
Wang Long said "this deadlock occurs three times in our environment"
[gthelen@google.com: v4]
Link: http://lkml.kernel.org/r/20180411084653.254724-1-gthelen@google.com
[akpm@linux-foundation.org: comment tweaks, struct initialization simplification]
Change-Id: Ibb773e8045852978f6207074491d262f1b3fb613
Link: http://lkml.kernel.org/r/20180410005908.167976-1-gthelen@google.com
Fixes: 682aa8e1a6 ("writeback: implement unlocked_inode_to_wb transaction and use it for stat updates")
Signed-off-by: Greg Thelen <gthelen@google.com>
Reported-by: Wang Long <wanglong19@meituan.com>
Acked-by: Wang Long <wanglong19@meituan.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: <stable@vger.kernel.org> [v4.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[natechancellor: Adjust context due to lack of b93b016313]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 54a307ba8d upstream.
When event on child inodes are sent to the parent inode mark and
parent inode mark was not marked with FAN_EVENT_ON_CHILD, the event
will not be delivered to the listener process. However, if the same
process also has a mount mark, the event to the parent inode will be
delivered regadless of the mount mark mask.
This behavior is incorrect in the case where the mount mark mask does
not contain the specific event type. For example, the process adds
a mark on a directory with mask FAN_MODIFY (without FAN_EVENT_ON_CHILD)
and a mount mark with mask FAN_CLOSE_NOWRITE (without FAN_ONDIR).
A modify event on a file inside that directory (and inside that mount)
should not create a FAN_MODIFY event, because neither of the marks
requested to get that event on the file.
Fixes: 1968f5eed5 ("fanotify: use both marks when possible")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
[natechancellor: Fix small conflict due to lack of 3cd5eca8d7]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit abc1be13fd upstream.
f2fs specifies the __GFP_ZERO flag for allocating some of its pages.
Unfortunately, the page cache also uses the mapping's GFP flags for
allocating radix tree nodes. It always masked off the __GFP_HIGHMEM
flag, and masks off __GFP_ZERO in some paths, but not all. That causes
radix tree nodes to be allocated with a NULL list_head, which causes
backtraces like:
__list_del_entry+0x30/0xd0
list_lru_del+0xac/0x1ac
page_cache_tree_insert+0xd8/0x110
The __GFP_DMA and __GFP_DMA32 flags would also be able to sneak through
if they are ever used. Fix them all by using GFP_RECLAIM_MASK at the
innermost location, and remove it from earlier in the callchain.
Link: http://lkml.kernel.org/r/20180411060320.14458-2-willy@infradead.org
Fixes: 449dd6984d ("mm: keep page cache radix tree nodes in check")
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reported-by: Chris Fries <cfries@google.com>
Debugged-by: Minchan Kim <minchan@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
