The kernel mount_block_root() function expects -EACESS or -EINVAL for a
unmountable filesystem when trying to mount the root with different
filesystem types.
However, in 5.3-rc1 the behavior when F2FS code cannot find valid block
changed to return -EFSCORRUPTED(-EUCLEAN), and this error code makes
mount_block_root() fail when trying to probe F2FS.
When the magic number of the superblock mismatches, it has a high
probability that it's just not a F2FS. In this case return -EINVAL seems
to be a better result, and this return value can make mount_block_root()
probing work again.
Return -EINVAL when the superblock has magic mismatch, -EFSCORRUPTED in
other cases (the magic matches but the superblock cannot be recognized).
Fixes: 10f966bbf521 ("f2fs: use generic EFSBADCRC/EFSCORRUPTED") Signed-off-by: Icenowy Zheng <icenowy@aosc.io> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Calling 'panic()' on a kernel with CONFIG_PREEMPT=y can leave the
calling CPU in an infinite loop, but with interrupts and preemption
enabled. From this state, userspace can continue to be scheduled,
despite the system being "dead" as far as the kernel is concerned.
This is easily reproducible on arm64 when booting with "nosmp" on the
command line; a couple of shell scripts print out a periodic "Ping"
message whilst another triggers a crash by writing to
/proc/sysrq-trigger:
Bail from the pci_driver probe function instead of from the drm_driver
load function.
This avoid /dev/dri/card0 temporarily getting registered and then
unregistered again, sending unwanted add / remove udev events to
userspace.
Specifically this avoids triggering the (userspace) bug fixed by this
plymouth merge-request:
https://gitlab.freedesktop.org/plymouth/plymouth/merge_requests/59
Note that despite that being an userspace bug, not sending unnecessary
udev events is a good idea in general.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1490490 Reviewed-by: Michel Dänzer <mdaenzer@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
We do check for a bad block during namespace init and that use
region bad block list. We need to initialize the bad block
for volatile regions for this to work. We also observe a lockdep
warning as below because the lock is not initialized correctly
since we skip bad block init for volatile regions.
When calling thermal_add_hwmon_sysfs(), the device type is sanitized by
replacing '-' with '_'. However tz->type remains unsanitized. Thus
calling thermal_hwmon_lookup_by_type() returns no device. And if there is
no device, thermal_remove_hwmon_sysfs() fails with "hwmon device lookup
failed!".
The result is unregisted hwmon devices in the sysfs.
Fixes: 409ef0bacacf ("thermal_hwmon: Sanitize attribute name passed to hwmon") Signed-off-by: Stefan Mavrodiev <stefan@olimex.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
integrity_kernel_read() can fail in which case we forward to call
ahash_request_free() on a currently running request. We have to wait
for its completion before we can free the request.
This was observed by interrupting a "find / -type f -xdev -print0 | xargs -0
cat 1>/dev/null" with ctrl-c on an IMA enabled filesystem.
clk_get_parent returns an error pointer upon failure, not NULL. So the
checks as they exist won't catch a failure. This patch changes the
checks and the return values to properly handle an error pointer.
Fixes: c4d8cfe516dc ("drm/msm/dsi: add implementation for helper functions") Cc: Sibi Sankar <sibis@codeaurora.org> Cc: Sean Paul <seanpaul@chromium.org> Cc: Rob Clark <robdclark@chromium.org> Cc: <stable@vger.kernel.org> # v4.19+ Signed-off-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
In a Resizable BAR Control Register, bits 13:8 control the size of the BAR.
The encoded values of these bits are as follows (see PCIe r5.0, sec
7.8.6.3):
Previously we incorrectly set the BAR size bits for a 1 MB BAR to 0x1f
instead of 0, so devices that support that size, e.g., new megaraid_sas and
mpt3sas adapters, fail to initialize during resume from S3 sleep.
Correctly calculate the BAR size bits for Resizable BAR control registers.
Link: https://lore.kernel.org/r/20190725192552.24295-1-sumit.saxena@broadcom.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203939 Fixes: d3252ace0bc6 ("PCI: Restore resized BAR state on resume") Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christian König <christian.koenig@amd.com> Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Recently, binutils had split Loongson-3 Extensions into four ASEs:
MMI, CAM, EXT, EXT2. This patch do the samething in kernel and expose
them in cpuinfo so applications can probe supported ASEs at runtime.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Huacai Chen <chenhc@lemote.com> Cc: Yunqiang Su <ysu@wavecomp.com> Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: linux-mips@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The current code would fail on huge pages addresses, since the shift would
be incorrect. Use the correct page shift value returned by
__find_linux_pte() to get the correct physical address. The code is more
generic and can handle both regular and compound pages.
When we are running multiple vcores on the same physical core, they
could be from different VMs and so it is possible that one of the
VMs could have its arch.mmu_ready flag cleared (for example by a
concurrent HPT resize) when we go to run it on a physical core.
We currently check the arch.mmu_ready flag for the primary vcore
but not the flags for the other vcores that will be run alongside
it. This adds that check, and also a check when we select the
secondary vcores from the preempted vcores list.
Cc: stable@vger.kernel.org # v4.14+ Fixes: 38c53af85306 ("KVM: PPC: Book3S HV: Fix exclusion between HPT resizing and other HPT updates") Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
VAG power control is improved to fit the manual [1]. This patch fixes as
minimum one bug: if customer muxes Headphone to Line-In right after boot,
the VAG power remains off that leads to poor sound quality from line-in.
I.e. after boot:
- Connect sound source to Line-In jack;
- Connect headphone to HP jack;
- Run following commands:
$ amixer set 'Headphone' 80%
$ amixer set 'Headphone Mux' LINE_IN
Change VAG power on/off control according to the following algorithm:
- turn VAG power ON on the 1st incoming event.
- keep it ON if there is any active VAG consumer (ADC/DAC/HP/Line-In).
- turn VAG power OFF when there is the latest consumer's pre-down event
come.
- always delay after VAG power OFF to avoid pop.
- delay after VAG power ON if the initiative consumer is Line-In, this
prevents pop during line-in muxing.
According to the data sheet [1], to avoid any pops/clicks,
the outputs should be muted during input/output
routing changes.
We currently don't validate the beacon head, i.e. the header,
fixed part and elements that are to go in front of the TIM
element. This means that the variable elements there can be
malformed, e.g. have a length exceeding the buffer size, but
most downstream code from this assumes that this has already
been checked.
Add the necessary checks to the netlink policy.
Cc: stable@vger.kernel.org Fixes: ed1b6cc7f80f ("cfg80211/nl80211: add beacon settings") Link: https://lore.kernel.org/r/1569009255-I7ac7fbe9436e9d8733439eab8acbbd35e55c74ef@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Enforce the first argument to be a correct type of a pointer to struct
element and avoid unnecessary typecasts from const to non-const pointers
(the change in validate_ie_attr() is needed to make this part work). In
addition, avoid signed/unsigned comparison within for_each_element() and
mark struct element packed just in case.
Signed-off-by: Jouni Malinen <j@w1.fi> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Rather than always iterating elements from frames with pure
u8 pointers, add a type "struct element" that encapsulates
the id/datalen/data format of them.
Then, add the element iteration macros
* for_each_element
* for_each_element_id
* for_each_element_extid
which take, as their first 'argument', such a structure and
iterate through a given u8 array interpreting it as elements.
While at it and since we'll need it, also add
* for_each_subelement
* for_each_subelement_id
* for_each_subelement_extid
which instead of taking data/length just take an outer element
and use its data/datalen.
Also add for_each_element_completed() to determine if any of
the loops above completed, i.e. it was able to parse all of
the elements successfully and no data remained.
Use for_each_element_id() in cfg80211_find_ie_match() as the
first user of this.
Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Synchronization is recommended before disabling the trace registers
to prevent any start or stop points being speculative at the point
of disabling the unit (section 7.3.77 of ARM IHI 0064D).
Synchronization is also recommended after programming the trace
registers to ensure all updates are committed prior to normal code
resuming (section 4.3.7 of ARM IHI 0064D).
Let's ensure these syncronization points are present in the code
and clearly commented.
Note that we could rely on the barriers in CS_LOCK and
coresight_disclaim_device_unlocked or the context switch to user
space - however coresight may be of use in the kernel.
On armv8 the mb macro is defined as dsb(sy) - Given that the etm4x is
only used on armv8 let's directly use dsb(sy) instead of mb(). This
removes some ambiguity and makes it easier to correlate the code with
the TRM.
Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[Fixed capital letter for "use" in title] Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20190829202842.580-11-mathieu.poirier@linaro.org Cc: stable@vger.kernel.org # 4.9+ Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Today, put_compat_statfs64() disallows nearly any field value over
2^32 if f_bsize is only 32 bits, but that makes no sense.
compat_statfs64 is there for the explicit purpose of providing 64-bit
fields for f_files, f_ffree, etc. And f_bsize is always only 32 bits.
As a result, 32-bit userspace gets -EOVERFLOW for i.e. large file
counts even with -D_FILE_OFFSET_BITS=64 set.
In reality, only f_bsize and f_frsize can legitimately overflow
(fields like f_type and f_namelen should never be large), so test
only those fields.
This bug was discussed at length some time ago, and this is the proposal
Al suggested at https://lkml.org/lkml/2018/8/6/640. It seemed to get
dropped amid the discussion of other related changes, but this
part seems obviously correct on its own, so I've picked it up and
sent it, for expediency.
Fixes: 64d2ab32efe3 ("vfs: fix put_compat_statfs64() does not handle errors") Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
prev_raw_counts is allocated when using intervals. This is used when
calculating the difference in the counts of events when using interval.
The current counts are stored in prev_raw_counts to calculate the
differences in the next iteration.
On the first interval of the second and subsequent repetitions,
prev_raw_counts would be the values stored in the last interval of the
previous repetitions, while the current counts will only be for the
first interval of the current repetition.
Hence there is a possibility of events showing up as big number.
Fix this by resetting prev_raw_counts whenever perf stat repeats the
command.
With the fix:
# perf stat -r 3 -I 2000 -e faults -e sched:sched_switch -a sleep 5
This was broken since the cset introducing the --interval feature, i.e.
--repeat + --interval wasn't tested at that point, add the Fixes tag so
that automatic scripts can pick this up.
Fixes: 13370a9b5bb8 ("perf stat: Add interval printing") Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Stephane Eranian <eranian@google.com> Cc: stable@vger.kernel.org # v3.9+ Link: http://lore.kernel.org/lkml/20190904094738.9558-2-srikar@linux.vnet.ibm.com
[ Fixed up conflicts with libperf, i.e. some perf_{evsel,evlist} lost the 'perf' prefix ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Observe a segmentation fault when 'perf stat' is asked to repeat forever
with the interval option.
Without fix:
# perf stat -r 0 -I 5000 -e cycles -a sleep 10
# time counts unit events
5.000211692 3,13,89,82,34,157 cycles
10.000380119 1,53,98,52,22,294 cycles
10.040467280 17,16,79,265 cycles
Segmentation fault
This problem was only observed when we use forever option aka -r 0 and
works with limited repeats. Calling print_counter with ts being set to
NULL, is not a correct option when interval is set. Hence avoid
print_counter(NULL,..) if interval is set.
Did the 'git bisect' to find the cset introducing the problem to add the
Fixes tag below, and at that time the problem reproduced as:
(gdb) run stat -r0 -I500 sleep 1
<SNIP>
Program received signal SIGSEGV, Segmentation fault.
print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866
866 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, csv_sep);
(gdb) bt
#0 print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866
#1 0x000000000041860a in print_counters (ts=ts@entry=0x0, argc=argc@entry=2, argv=argv@entry=0x7fffffffd640) at builtin-stat.c:938
#2 0x0000000000419a7f in cmd_stat (argc=2, argv=0x7fffffffd640, prefix=<optimized out>) at builtin-stat.c:1411
#3 0x000000000045c65a in run_builtin (p=p@entry=0x6291b8 <commands+216>, argc=argc@entry=5, argv=argv@entry=0x7fffffffd640) at perf.c:370
#4 0x000000000045c893 in handle_internal_command (argc=5, argv=0x7fffffffd640) at perf.c:429
#5 0x000000000045c8f1 in run_argv (argcp=argcp@entry=0x7fffffffd4ac, argv=argv@entry=0x7fffffffd4a0) at perf.c:473
#6 0x000000000045cac9 in main (argc=<optimized out>, argv=<optimized out>) at perf.c:588
(gdb)
Mostly the same as just before this patch:
Program received signal SIGSEGV, Segmentation fault.
0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964
964 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, config->csv_sep);
(gdb) bt
#0 0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964
#1 0x0000000000588047 in perf_evlist__print_counters (evlist=0xbc9b90, config=0xa1f2a0 <stat_config>, _target=0xa1f0c0 <target>, ts=0x0, argc=2, argv=0x7fffffffd670)
at util/stat-display.c:1172
#2 0x000000000045390f in print_counters (ts=0x0, argc=2, argv=0x7fffffffd670) at builtin-stat.c:656
#3 0x0000000000456bb5 in cmd_stat (argc=2, argv=0x7fffffffd670) at builtin-stat.c:1960
#4 0x00000000004dd2e0 in run_builtin (p=0xa30e00 <commands+288>, argc=5, argv=0x7fffffffd670) at perf.c:310
#5 0x00000000004dd54d in handle_internal_command (argc=5, argv=0x7fffffffd670) at perf.c:362
#6 0x00000000004dd694 in run_argv (argcp=0x7fffffffd4cc, argv=0x7fffffffd4c0) at perf.c:406
#7 0x00000000004dda11 in main (argc=5, argv=0x7fffffffd670) at perf.c:531
(gdb)
Fixes: d4f63a4741a8 ("perf stat: Introduce print_counters function") Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # v4.2+ Link: http://lore.kernel.org/lkml/20190904094738.9558-3-srikar@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
We release wrong pointer on error path in cpu_cache_level__read
function, leading to segfault:
(gdb) r record ls
Starting program: /root/perf/tools/perf/perf record ls
...
[ perf record: Woken up 1 times to write data ]
double free or corruption (out)
Thread 1 "perf" received signal SIGABRT, Aborted.
0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6
(gdb) bt
#0 0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6
#1 0x00007ffff7443bac in abort () from /lib64/power9/libc.so.6
#2 0x00007ffff74af8bc in __libc_message () from /lib64/power9/libc.so.6
#3 0x00007ffff74b92b8 in malloc_printerr () from /lib64/power9/libc.so.6
#4 0x00007ffff74bb874 in _int_free () from /lib64/power9/libc.so.6
#5 0x0000000010271260 in __zfree (ptr=0x7fffffffa0b0) at ../../lib/zalloc..
#6 0x0000000010139340 in cpu_cache_level__read (cache=0x7fffffffa090, cac..
#7 0x0000000010143c90 in build_caches (cntp=0x7fffffffa118, size=<optimiz..
...
Releasing the proper pointer.
Fixes: 720e98b5faf1 ("perf tools: Add perf data cache feature") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org: # v4.6+ Link: http://lore.kernel.org/lkml/20190912105235.10689-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
When a cpu requests broadcasting, before starting the tick broadcast
hrtimer, bc_set_next() checks if the timer callback (bc_handler) is active
using hrtimer_try_to_cancel(). But hrtimer_try_to_cancel() does not provide
the required synchronization when the callback is active on other core.
The callback could have already executed tick_handle_oneshot_broadcast()
and could have also returned. But still there is a small time window where
the hrtimer_try_to_cancel() returns -1. In that case bc_set_next() returns
without doing anything, but the next_event of the tick broadcast clock
device is already set to a timeout value.
In the race condition diagram below, CPU #1 is running the timer callback
and CPU #2 is entering idle state and so calls bc_set_next().
In the worst case, the next_event will contain an expiry time, but the
hrtimer will not be started which happens when the racing callback returns
HRTIMER_NORESTART. The hrtimer might never recover if all further requests
from the CPUs to subscribe to tick broadcast have timeout greater than the
next_event of tick broadcast clock device. This leads to cascading of
failures and finally noticed as rcu stall warnings
Here is a depiction of the race condition
CPU #1 (Running timer callback) CPU #2 (Enter idle
and subscribe to
tick broadcast)
--------------------- ---------------------
__run_hrtimer() tick_broadcast_enter()
bc_handler() __tick_broadcast_oneshot_control()
tick_handle_oneshot_broadcast()
raw_spin_lock(&tick_broadcast_lock);
dev->next_event = KTIME_MAX; //wait for tick_broadcast_lock
//next_event for tick broadcast clock
set to KTIME_MAX since no other cores
subscribed to tick broadcasting
raw_spin_unlock(&tick_broadcast_lock);
if (dev->next_event == KTIME_MAX)
return HRTIMER_NORESTART
// callback function exits without
restarting the hrtimer //tick_broadcast_lock acquired
raw_spin_lock(&tick_broadcast_lock);
tick_broadcast_set_event()
clockevents_program_event()
dev->next_event = expires;
bc_set_next()
hrtimer_try_to_cancel()
//returns -1 since the timer
callback is active. Exits without
restarting the timer
cpu_base->running = NULL;
The comment that hrtimer cannot be armed from within the callback is
wrong. It is fine to start the hrtimer from within the callback. Also it is
safe to start the hrtimer from the enter/exit idle code while the broadcast
handler is active. The enter/exit idle code and the broadcast handler are
synchronized using tick_broadcast_lock. So there is no need for the
existing try to cancel logic. All this can be removed which will eliminate
the race condition as well.
Fixes: 5d1638acb9f6 ("tick: Introduce hrtimer based broadcast") Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190926135101.12102-2-balasubramani_vivekanandan@mentor.com Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
If the re-allocation of tep->cmdlines succeeds, then the previous
allocation of tep->cmdlines will be freed. If we later fail in
add_new_comm(), we must not free cmdlines, and also should assign
tep->cmdlines to the new allocation. Otherwise when freeing tep, the
tep->cmdlines will be pointing to garbage.
Fixes: a6d2a61ac653a ("tools lib traceevent: Remove some die() calls") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: linux-trace-devel@vger.kernel.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20190828191819.970121417@goodmis.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The calls to arch_add_memory()/arch_remove_memory() are always made
with the read-side cpu_hotplug_lock acquired via memory_hotplug_begin().
On pSeries, arch_add_memory()/arch_remove_memory() eventually call
resize_hpt() which in turn calls stop_machine() which acquires the
read-side cpu_hotplug_lock again, thereby resulting in the recursive
acquisition of this lock.
In the absence of CONFIG_PROVE_LOCKING, we hadn't observed a system
lockup during a memory hotplug operation because cpus_read_lock() is a
per-cpu rwsem read, which, in the fast-path (in the absence of the
writer, which in our case is a CPU-hotplug operation) simply
increments the read_count on the semaphore. Thus a recursive read in
the fast-path doesn't cause any problems.
However, we can hit this problem in practice if there is a concurrent
CPU-Hotplug operation in progress which is waiting to acquire the
write-side of the lock. This will cause the second recursive read to
block until the writer finishes. While the writer is blocked since the
first read holds the lock. Thus both the reader as well as the writers
fail to make any progress thereby blocking both CPU-Hotplug as well as
Memory Hotplug operations.
Memory-Hotplug CPU-Hotplug
CPU 0 CPU 1
------ ------
that limited the number of devices to 256. Before the patch we could
create 1000s of devices, but the patch switched us from using our
own thread to using a work queue which has a default limit of 256
active works.
The problem is that our recv_work function sits in a loop until
disconnection but only handles IO for one connection. The work is
started when the connection is started/restarted, but if we end up
creating 257 or more connections, the queue_work call just queues
connection257+'s recv_work and that waits for connection 1 - 256's
recv_work to be disconnected and that work instance completing.
Instead of reverting back to kthreads, this has us allocate a
workqueue_struct per device, so we can block in the work.
Cc: stable@vger.kernel.org Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
This will allow the blksize to be set zero and then use 1024 as
default.
Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Xiubo Li <xiubli@redhat.com>
[fix to use goto out instead of return in genl_connect] Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
When a vCPU is brought done, the XIVE VP (Virtual Processor) is first
disabled and then the event notification queues are freed. When freeing
the queues, we check for possible escalation interrupts and free them
also.
But when a XIVE VP is disabled, the underlying XIVE ENDs also are
disabled in OPAL. When an END (Event Notification Descriptor) is
disabled, its ESB pages (ESn and ESe) are disabled and loads return all
1s. Which means that any access on the ESB page of the escalation
interrupt will return invalid values.
When an interrupt is freed, the shutdown handler computes a 'saved_p'
field from the value returned by a load in xive_do_source_set_mask().
This value is incorrect for escalation interrupts for the reason
described above.
This has no impact on Linux/KVM today because we don't make use of it
but we will introduce in future changes a xive_get_irqchip_state()
handler. This handler will use the 'saved_p' field to return the state
of an interrupt and 'saved_p' being incorrect, softlockup will occur.
Fix the vCPU cleanup sequence by first freeing the escalation interrupts
if any, then disable the XIVE VP and last free the queues.
Fixes: 90c73795afa2 ("KVM: PPC: Book3S HV: Add a new KVM device for the XIVE native exploitation mode") Fixes: 5af50993850a ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190806172538.5087-1-clg@kaod.org Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
An oops can be triggered in the scheduler when running qemu on arm64:
Unable to handle kernel paging request at virtual address ffff000008effe40
Internal error: Oops: 96000007 [#1] SMP
Process migration/0 (pid: 12, stack limit = 0x00000000084e3736)
pstate: 20000085 (nzCv daIf -PAN -UAO)
pc : __ll_sc___cmpxchg_case_acq_4+0x4/0x20
lr : move_queued_task.isra.21+0x124/0x298
...
Call trace:
__ll_sc___cmpxchg_case_acq_4+0x4/0x20
__migrate_task+0xc8/0xe0
migration_cpu_stop+0x170/0x180
cpu_stopper_thread+0xec/0x178
smpboot_thread_fn+0x1ac/0x1e8
kthread+0x134/0x138
ret_from_fork+0x10/0x18
__set_cpus_allowed_ptr() will choose an active dest_cpu in affinity mask to
migrage the process if process is not currently running on any one of the
CPUs specified in affinity mask. __set_cpus_allowed_ptr() will choose an
invalid dest_cpu (dest_cpu >= nr_cpu_ids, 1024 in my virtual machine) if
CPUS in an affinity mask are deactived by cpu_down after cpumask_intersects
check. cpumask_test_cpu() of dest_cpu afterwards is overflown and may pass if
corresponding bit is coincidentally set. As a consequence, kernel will
access an invalid rq address associate with the invalid CPU in
migration_cpu_stop->__migrate_task->move_queued_task and the Oops occurs.
The reproduce the crash:
1) A process repeatedly binds itself to cpu0 and cpu1 in turn by calling
sched_setaffinity.
2) A shell script repeatedly does "echo 0 > /sys/devices/system/cpu/cpu1/online"
and "echo 1 > /sys/devices/system/cpu/cpu1/online" in turn.
3) Oops appears if the invalid CPU is set in memory after tested cpumask.
Signed-off-by: KeMeng Shi <shikemeng@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/1568616808-16808-1-git-send-email-shikemeng@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
thermal_zone_device_unregister() cancels the delayed work that polls the
thermal zone, but it does not wait for it to finish. This is racy with
respect to the freeing of the thermal zone device, which can result in a
use-after-free [1].
Fix this by waiting for the delayed work to finish before freeing the
thermal zone device. Note that thermal_zone_device_set_polling() is
never invoked from an atomic context, so it is safe to call
cancel_delayed_work_sync() that can block.
[1]
[ +0.002221] ==================================================================
[ +0.000064] BUG: KASAN: use-after-free in __mutex_lock+0x1076/0x11c0
[ +0.000016] Read of size 8 at addr ffff8881e48e0450 by task kworker/1:0/17
LPTimer can use a 32KHz clock for counting. It depends on clock tree
configuration. In such a case, PWM output frequency range is limited.
Although unlikely, nothing prevents user from requesting a PWM frequency
above counting clock (32KHz for instance):
- This causes (prd - 1) = 0xffff to be written in ARR register later in
the apply() routine.
This results in badly configured PWM period (and also duty_cycle).
Add a check to report an error is such a case.
IF the server rejected our layout return with a state error such as
NFS4ERR_BAD_STATEID, or even a stale inode error, then we do want
to clear out all the remaining layout segments and mark that stateid
as invalid.
Fixes: 1c5bd76d17cca ("pNFS: Enable layoutreturn operation for...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Do not try to allocate any amount of memory requested by the user.
Instead limit it to 128 registers. Actually the longest series of
consecutive allowed registers are 48, mmGB_TILE_MODE0-31 and
mmGB_MACROTILE_MODE0-15 (0x2644-0x2673).
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=111273 Signed-off-by: Trek <trek00@inbox.ru> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
... this works:
nft add rule ip filter input add @set1 { ip saddr }
-> whenever rule is triggered, the source ip address is inserted
into the set (if it did not exist).
This won't work:
nft add rule ip filter input ip saddr @set1 counter
Error: Could not process rule: Operation not supported
In other words, we can add entries to the set, but then can't make
matching decision based on that set.
That is just wrong -- all set backends support lookups (else they would
not be very useful).
The failure comes from an explicit rejection in nft_lookup.c.
Looking at the history, it seems like NFT_SET_EVAL used to mean
'set contains expressions' (aka. "is a meter"), for instance something like
nft add rule ip filter input meter example { ip saddr limit rate 10/second }
or
nft add rule ip filter input meter example { ip saddr counter }
The actual meaning of NFT_SET_EVAL however, is
'set can be updated from the packet path'.
'meters' and packet-path insertions into sets, such as
'add @set { ip saddr }' use exactly the same kernel code (nft_dynset.c)
and thus require a set backend that provides the ->update() function.
The only set that provides this also is the only one that has the
NFT_SET_EVAL feature flag.
Removing the wrong check makes the above example work.
While at it, also fix the flag check during set instantiation to
allow supported combinations only.
Fixes: 8aeff920dcc9b3f ("netfilter: nf_tables: add stateful object reference to set elements") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
If client mds session is evicted in CEPH_MDS_SESSION_OPENING state,
mds won't send session msg to client, and delayed_work skip
CEPH_MDS_SESSION_OPENING state session, the session hang forever.
Allow ceph_con_keepalive to reconnect a session in OPENING to avoid
session hang. Also, ensure that we skip sessions in RESTARTING and
REJECTED states since those states can't be resurrected by issuing
a keepalive.
When filling an inode with info from the MDS, i_blkbits is being
initialized using fl_stripe_unit, which contains the stripe unit in
bytes. Unfortunately, this doesn't make sense for directories as they
have fl_stripe_unit set to '0'. This means that i_blkbits will be set
to 0xff, causing an UBSAN undefined behaviour in i_blocksize():
UBSAN: Undefined behaviour in ./include/linux/fs.h:731:12
shift exponent 255 is too large for 32-bit type 'int'
Fix this by initializing i_blkbits to CEPH_BLOCK_SHIFT if fl_stripe_unit
is zero.
Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
If MCFG area is not reserved in E820, Xen by default will defer its usage
until Dom0 registers it explicitly after ACPI parser recognizes it as
a reserved resource in DSDT. Having it reserved in E820 is not
mandatory according to "PCI Firmware Specification, rev 3.2" (par. 4.1.2)
and firmware is free to keep a hole in E820 in that place. Xen doesn't know
what exactly is inside this hole since it lacks full ACPI view of the
platform therefore it's potentially harmful to access MCFG region
without additional checks as some machines are known to provide
inconsistent information on the size of the region.
Now xen_mcfg_late() runs after acpi_init() which is too late as some basic
PCI enumeration starts exactly there as well. Trying to register a device
prior to MCFG reservation causes multiple problems with PCIe extended
capability initializations in Xen (e.g. SR-IOV VF BAR sizing). There are
no convenient hooks for us to subscribe to so register MCFG areas earlier
upon the first invocation of xen_add_device(). It should be safe to do once
since all the boot time buses must have their MCFG areas in MCFG table
already and we don't support PCI bus hot-plug.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Currently on mmap cache policy, we always attach writeback_fid
whether mmap type is SHARED or PRIVATE. However, in the use case
of kata-container which combines 9p(Guest OS) with overlayfs(Host OS),
this behavior will trigger overlayfs' copy-up when excute command
inside container.
In encode_attrs(), there is an if statement on line 1145 to check
whether label is NULL:
if (label && (attrmask[2] & FATTR4_WORD2_SECURITY_LABEL))
When label is NULL, it is used on lines 1178-1181:
*p++ = cpu_to_be32(label->lfs);
*p++ = cpu_to_be32(label->pi);
*p++ = cpu_to_be32(label->len);
p = xdr_encode_opaque_fixed(p, label->label, label->len);
To fix these bugs, label is checked before being used.
These bugs are found by a static analysis tool STCheck written by us.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
integrity_kernel_read() returns the number of bytes read. If this is
a short read then this positive value is returned from
ima_calc_file_hash_atfm(). Currently this is only indirectly called from
ima_calc_file_hash() and this function only tests for the return value
being zero or nonzero and also doesn't forward the return value.
Nevertheless there's no point in returning a positive value as an error,
so translate a short read into -EINVAL.
In a few places we don't properly initialize on-stack chandefs,
resulting in EDMG data to be non-zero, which broke things.
Additionally, in a few places we rely on the driver to init the
data completely, but perhaps we shouldn't as non-EDMG drivers
may not initialize the EDMG data, also initialize it there.
Cc: stable@vger.kernel.org Fixes: 2a38075cd0be ("nl80211: Add support for EDMG channels") Reported-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Link: https://lore.kernel.org/r/1569239475-I2dcce394ecf873376c386a78f31c2ec8b538fa25@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
In case a user process using xenbus has open transactions and is killed
e.g. via ctrl-C the following cleanup of the allocated resources might
result in a deadlock due to trying to end a transaction in the xenbus
worker thread:
This patch reverts commit 75437bb304b20 (locking/pvqspinlock: Don't
wait if vCPU is preempted). A large performance regression was caused
by this commit. on over-subscription scenarios.
The test was run on a Xeon Skylake box, 2 sockets, 40 cores, 80 threads,
with three VMs of 80 vCPUs each. The score of ebizzy -M is reduced from
13000-14000 records/s to 1700-1800 records/s:
Exit from aggressive wait-early mechanism can result in premature yield
and extra scheduling latency.
Actually, only 6% of wait_early events are caused by vcpu_is_preempted()
being true. However, when one vCPU voluntarily releases its vCPU, all
the subsequently waiters in the queue will do the same and the cascading
effect leads to bad performance.
kvm optimizations:
[1] commit d73eb57b80b (KVM: Boost vCPUs that are delivering interrupts)
[2] commit 266e85a5ec9 (KVM: X86: Boost queue head vCPU to mitigate lock waiter preemption)
Tested-by: loobinliu@tencent.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Waiman Long <longman@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: loobinliu@tencent.com Cc: stable@vger.kernel.org Fixes: 75437bb304b20 (locking/pvqspinlock: Don't wait if vCPU is preempted) Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
We must not unconditionally set the DMA snoop bit; if the DMA API is
assuming that the device is not DMA coherent, and the device snoops the
CPU caches, the device can see stale cache lines brought in by
speculative prefetch.
This leads to the device seeing stale data, potentially resulting in
corrupted data transfers. Commonly, this results in a descriptor fetch
error such as:
but can lead to other errors, and potentially direct the SDHCI
controller to read/write data to other memory locations (e.g. if a valid
descriptor is visible to the device in a stale cache line.)
Fix this by ensuring that the DMA snoop bit corresponds with the
behaviour of the DMA API. Since the driver currently only supports DT,
use of_dma_is_coherent(). Note that device_get_dma_attr() can not be
used as that risks re-introducing this bug if/when the driver is
converted to ACPI.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
ADMA errors are potentially data corrupting events; although we print
the register state, we do not usefully print the ADMA descriptors.
Worse than that, we print them by referencing their virtual address
which is meaningless when the register state gives us the DMA address
of the failing descriptor.
Print the ADMA descriptors giving their DMA addresses rather than their
virtual addresses, and print them using SDHCI_DUMP() rather than DBG().
We also do not show the correct value of the interrupt status register;
the register dump shows the current value, after we have cleared the
pending interrupts we are going to service. What is more useful is to
print the interrupts that _were_ pending at the time the ADMA error was
encountered. Fix that too.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The OMAP36xx and AM/DM37x TRMs say that the maximum divider for DSS fclk
(in CM_CLKSEL_DSS) is 32. Experimentation shows that this is not
correct, and using divider of 32 breaks DSS with a flood or underflows
and sync losts. Dividers up to 31 seem to work fine.
There is another patch to the DT files to limit the divider correctly,
but as the DSS driver also needs to know the maximum divider to be able
to iteratively find good rates, we also need to do the fix in the DSS
driver.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Adam Ford <aford173@gmail.com> Cc: stable@vger.kernel.org Link: https://patchwork.freedesktop.org/patch/msgid/20191002122542.8449-1-tomi.valkeinen@ti.com Tested-by: Adam Ford <aford173@gmail.com> Reviewed-by: Jyri Sarha <jsarha@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Converting from ms to s requires dividing by 1000, not multiplying. So
this is currently taking the smaller of new_timeout and 1.28e8,
i.e. effectively new_timeout.
The driver knows what it set max_hw_heartbeat_ms to, so use that
value instead of doing a division at run-time.
FWIW, this can easily be tested by booting into a busybox shell and
doing "watchdog -t 5 -T 130 /dev/watchdog" - without this patch, the
watchdog fires after 130&127 == 2 seconds.
Fixes: b07e228eee69 "watchdog: imx2_wdt: Fix set_timeout for big timeout values" Cc: stable@vger.kernel.org # 5.2 plus anything the above got backported to Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20190812131356.23039-1-linux@rasmusvillemoes.dk Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The reason is that the code in collect_expired_timers() uses jiffies
unprotected:
if (next_event > jiffies)
base->clk = jiffies;
As the compiler is allowed to reload the value base->clk can advance
between the check and the store and in the worst case advance farther than
next event. That causes the timer expiry to be delayed until the wheel
pointer wraps around.
Convert the code to use READ_ONCE()
Fixes: 236968383cf5 ("timers: Optimize collect_expired_timers() for NOHZ") Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Liang ZhiCheng <liangzhicheng@baidu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1568894687-14499-1-git-send-email-lirongqing@baidu.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
all execve()s will fail due to argv copying into kmap()ed pages, and on
usercopy checking the calls ultimately of virt_to_page() will be looking
for "bad" kmap (highmem) pointers due to CONFIG_DEBUG_VIRTUAL=y:
kaddr = kmap(kmapped_page);
...
if (copy_from_user(kaddr+offset, str, bytes_to_copy)) ...
Now we can fetch the correct page to avoid the pfn check. In both cases,
hardened usercopy will need to walk the page-span checker (if enabled)
to do sanity checking.
Reported-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Fixes: f5509cc18daa ("mm: Hardened usercopy") Cc: Matthew Wilcox <willy@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/201909171056.7F2FFD17@keescook Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
IV transfer from ofifo to class2 (set up at [29][30]) is not guaranteed
to be scheduled before the data transfer from ofifo to external memory
(set up at [38]:
If ofifo -> external memory transfer happens first, DECO will hang
(issuing a Watchdog Timeout error, if WDOG is enabled) waiting for
data availability in ofifo for the ofifo -> c2 ififo transfer.
Make sure IV transfer happens first by waiting for all CAAM internal
transfers to end before starting payload transfer.
New descriptor with jump command inserted at [37]:
[Note: the issue is present in the descriptor from the very beginning
(cf. Fixes tag). However I've marked it v4.19+ since it's the oldest
maintained kernel that the patch applies clean against.]
skcipher_walk_done may be called with an error by internal or
external callers. For those internal callers we shouldn't unmap
pages but for external callers we must unmap any pages that are
in use.
This patch distinguishes between the two cases by checking whether
walk->nbytes is zero or not. For internal callers, we now set
walk->nbytes to zero prior to the call. For external callers,
walk->nbytes has always been non-zero (as zero is used to indicate
the termination of a walk).
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Fixes: 5cde0af2a982 ("[CRYPTO] cipher: Added block cipher type") Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
It seems that smp_processor_id() is only used for a best-effort
load-balancing, refer to qat_crypto_get_instance_node(). It's not feasible
to disable preemption for the duration of the crypto requests. Therefore,
just silence the warning. This commit is similar to e7a9b05ca4
("crypto: cavium - Fix smp_processor_id() warnings").
Silences the following splat:
BUG: using smp_processor_id() in preemptible [00000000] code: cryptomgr_test/2904
caller is qat_alg_ablkcipher_setkey+0x300/0x4a0 [intel_qat]
CPU: 1 PID: 2904 Comm: cryptomgr_test Tainted: P O 4.14.69 #1
...
Call Trace:
dump_stack+0x5f/0x86
check_preemption_disabled+0xd3/0xe0
qat_alg_ablkcipher_setkey+0x300/0x4a0 [intel_qat]
skcipher_setkey_ablkcipher+0x2b/0x40
__test_skcipher+0x1f3/0xb20
? cpumask_next_and+0x26/0x40
? find_busiest_group+0x10e/0x9d0
? preempt_count_add+0x49/0xa0
? try_module_get+0x61/0xf0
? crypto_mod_get+0x15/0x30
? __kmalloc+0x1df/0x1f0
? __crypto_alloc_tfm+0x116/0x180
? crypto_skcipher_init_tfm+0xa6/0x180
? crypto_create_tfm+0x4b/0xf0
test_skcipher+0x21/0xa0
alg_test_skcipher+0x3f/0xa0
alg_test.part.6+0x126/0x2a0
? finish_task_switch+0x21b/0x260
? __schedule+0x1e9/0x800
? __wake_up_common+0x8d/0x140
cryptomgr_test+0x40/0x50
kthread+0xff/0x130
? cryptomgr_notify+0x540/0x540
? kthread_create_on_node+0x70/0x70
ret_from_fork+0x24/0x50
Fixes: ed8ccaef52 ("crypto: qat - Add support for SRIOV") Cc: stable@vger.kernel.org Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The tools/lib/traceevent/Makefile had a test added to it to detect a failure
of the "nm" when making the dynamic list file (whatever that is). The
problem is that the test sorts the values "U W w" and some versions of sort
will place "w" ahead of "W" (even though it has a higher ASCII value, and
break the test.
Add 'tr "w" "W"' to merge the two and not worry about the ordering.
Reported-by: Tzvetomir Stoyanov <tstoyanov@vmware.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Michal rarek <mmarek@suse.com> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Wang Nan <wangnan0@huawei.com> Cc: stable@vger.kernel.org Fixes: 6467753d61399 ("tools lib traceevent: Robustify do_generate_dynamic_list_file") Link: http://lkml.kernel.org/r/20190805130150.25acfeb1@gandalf.local.home Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The kHz to Hz is incorrectly converted in a few places in the code,
this results in a wrong frequency being calculated because devfreq core
uses OPP frequencies that are given in Hz to clamp the rate, while
tegra-devfreq gives to the core value in kHz and then it also expects to
receive value in kHz from the core. In a result memory freq is always set
to a value which is close to ULONG_MAX because of the bug. Hence the EMC
frequency is always capped to the maximum and the driver doesn't do
anything useful. This patch was tested on Tegra30 and Tegra124 SoC's, EMC
frequency scaling works properly now.
On POWER9, when userspace reads the value of the DPDES register on a
vCPU, it is possible for 0 to be returned although there is a doorbell
interrupt pending for the vCPU. This can lead to a doorbell interrupt
being lost across migration. If the guest kernel uses doorbell
interrupts for IPIs, then it could malfunction because of the lost
interrupt.
This happens because a newly-generated doorbell interrupt is signalled
by setting vcpu->arch.doorbell_request to 1; the DPDES value in
vcpu->arch.vcore->dpdes is not updated, because it can only be updated
when holding the vcpu mutex, in order to avoid races.
To fix this, we OR in vcpu->arch.doorbell_request when reading the
DPDES value.
Cc: stable@vger.kernel.org # v4.13+ Fixes: 579006944e0d ("KVM: PPC: Book3S HV: Virtualize doorbell facility on POWER9") Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
ccw console is created early in start_kernel and used before css is
initialized or ccw console subchannel is registered. Until then console
subchannel does not have a parent. For that reason assume subchannels
with no parent are not pseudo subchannels. This fixes the following
kasan finding:
BUG: KASAN: global-out-of-bounds in sch_is_pseudo_sch+0x8e/0x98
Read of size 8 at addr 00000000000005e8 by task swapper/0/0
Fix the following kasan finding:
BUG: KASAN: global-out-of-bounds in ccwgroup_create_dev+0x850/0x1140
Read of size 1 at addr 0000000000000000 by task systemd-udevd.r/561
If the KVM_S390_MEM_OP ioctl is called with an access register >= 16,
then there is certainly a bug in the calling userspace application.
We check for wrong access registers, but only if the vCPU was already
in the access register mode before (i.e. the SIE block has recorded
it). The check is also buried somewhere deep in the calling chain (in
the function ar_translation()), so this is somewhat hard to find.
It's better to always report an error to the userspace in case this
field is set wrong, and it's safer in the KVM code if we block wrong
values here early instead of relying on a check somewhere deep down
the calling chain, so let's add another check to kvm_s390_guest_mem_op()
directly.
We also should check that the "size" is non-zero here (thanks to Janosch
Frank for the hint!). If we do not check the size, we could call vmalloc()
with this 0 value, and this will cause a kernel warning.
Signed-off-by: Thomas Huth <thuth@redhat.com> Link: https://lkml.kernel.org/r/20190829122517.31042-1-thuth@redhat.com Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
With THREAD_INFO_IN_TASK (which is selected on s390) task's stack usage
is refcounted and should always be protected by get/put when touching
other task's stack to avoid race conditions with task's destruction code.
This commit has caused failure to launch 64-bit linux VMs when kvm-intel
ept module parameter is off. It is off by default on old Intel CPUs.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Acked-by: Tyler Hicks <tyhicks@canonical.com> Acked-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
BugLink: https://launchpad.net/bugs/1852141
When a jump_whitelist bitmap is reused, it needs to be cleared.
Currently this is done with memset() and the size calculation assumes
bitmaps are made of 32-bit words, not longs. So on 64-bit
architectures, only the first half of the bitmap is cleared.
If some whitelist bits are carried over between successive batches
submitted on the same context, this will presumably allow embedding
the rogue instructions that we're trying to reject.
Use bitmap_zero() instead, which gets the calculation right.
Fixes: f8c08d8faee5 ("drm/i915/cmdparser: Add support for backward jumps") Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
CVE-2019-0155
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Jack Wang [Mon, 7 Oct 2019 12:36:53 +0000 (14:36 +0200)]
KVM: nVMX: handle page fault in vmread fix
BugLink: https://launchpad.net/bugs/1851205
During backport f7eea636c3d5 ("KVM: nVMX: handle page fault in vmread"),
there was a mistake the exception reference should be passed to function
kvm_write_guest_virt_system, instead of NULL, other wise, we will get
NULL pointer deref, eg
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 5ff375e9dcb5a9ec75f460aaa61fd605a731dda9 linux-stable) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
[tyhicks Backport to 5.0
- Minor context adjustment due to missing kvm_set_mmio_spte_mask()] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Tyler Hicks [Fri, 1 Nov 2019 15:21:39 +0000 (15:21 +0000)]
UBUNTU: SAUCE: cpu/speculation: Uninline and export CPU mitigations helpers
A kernel module may need to check the value of the "mitigations=" kernel
command line parameter as part of its setup when the module needs
to perform software mitigations for a CPU flaw. Uninline and export the
helper functions surrounding the cpu_mitigations enum to allow for their
usage from a module. Lastly, privatize the enum and cpu_mitigations
variable since the value of cpu_mitigations can be checked with the
exported helper functions.
Junaid Shahid [Thu, 31 Oct 2019 23:33:47 +0000 (00:33 +0100)]
UBUNTU: SAUCE: kvm: x86: mmu: Recovery of shattered NX large pages
The page table pages corresponding to broken down large pages are
zapped in FIFO order, so that the large page can potentially
be recovered, if it is no longer being used for execution. This removes
the performance penalty for walking deeper EPT page tables.
By default, one large page will last about one hour once the guest
reaches a steady state.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
[tyhicks: Backport to 4.15
- Minor context adjustments due to different members of struct
kvm_mmu_page and kvm_arch] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Junaid Shahid [Thu, 31 Oct 2019 23:33:46 +0000 (00:33 +0100)]
UBUNTU: SAUCE: kvm: Add helper function for creating VM worker threads
This adds a function to create a kernel thread associated with a given
VM. In particular, it ensures that the worker thread inherits the
priority and cgroups of the calling thread.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
[tyhicks: Backport to 4.15
- Fix up conflicts in #includes of kvm_main.c
- Minor context adjustments in kvm_host.h] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Thu, 31 Oct 2019 23:33:45 +0000 (00:33 +0100)]
UBUNTU: SAUCE: kvm: mmu: ITLB_MULTIHIT mitigation
With some Intel processors, putting the same virtual address in the TLB
as both a 4 KiB and 2 MiB page can confuse the instruction fetch unit
and cause the processor to issue a machine check. Unfortunately if EPT
page tables use huge pages, it possible for a malicious guest to cause
this situation.
This patch adds a knob to mark huge pages as non-executable. When the
nx_huge_pages parameter is enabled (and we are using EPT), all huge pages
are marked as NX. If the guest attempts to execute in one of those pages,
the page is broken down into 4K pages, which are then marked executable.
This is not an issue for shadow paging (except nested EPT), because then
the host is in control of TLB flushes and the problematic situation cannot
happen. With nested EPT, again the nested guest can cause problems so we
treat shadow and direct EPT the same.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
[tyhicks: Backport to 4.15
- Context adjustments due to missing mmio_cached and unsync members of
struct kvm_mmu_page and missing kvm_set_mmio_spte_mask()
- Call kvm_mmu_invalidate_zap_all_pages() instead of
kvm_mmu_zap_all_fast() since the latter does not exist] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Some processors may incur a machine check error possibly
resulting in an unrecoverable cpu hang when an instruction fetch
encounters a TLB multi-hit in the instruction TLB. This can occur
when the page size is changed along with either the physical
address or cache type [1].
This issue affects both bare-metal x86 page tables and EPT.
This can be mitigated by either eliminating the use of large
pages or by using careful TLB invalidations when changing the
page size in the page tables.
Just like Spectre, Meltdown, L1TF and MDS, a new bit has been
allocated in MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will
be set on CPUs which are mitigated against this issue.
[1] For example please refer to erratum SKL002 in "6th Generation
Intel Processor Family Specification Update"
https://www.intel.com/content/www/us/en/products/docs/processors/core/desktop-6th-gen-core-family-spec-update.html
https://www.google.com/search?q=site:intel.com+SKL002
There are a lot of other affected processors outside of Skylake and
that the erratum(referred above) does not fully disclose the issue
and the impact, both on Skylake and across all the affected CPUs.
[tyhicks: Backport to 4.15
- ATOM_SILVERMONT_D is ATOM_SILVERMONT_X
- ATOM_AIRMONT_NP does not yet exist
- ATOM_GOLDMONT_D is ATOM_GOLDMONT_X
- Hygon isn't supported to VULNWL_HYGON() does not exist] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Sun, 27 Oct 2019 15:23:23 +0000 (16:23 +0100)]
UBUNTU: SAUCE: KVM: vmx, svm: always run with EFER.NXE=1 when shadow paging is active
VMX already does so if the host has SMEP, in order to support the combination of
CR0.WP=1 and CR4.SMEP=1. However, it is perfectly safe to always do so, and in
fact VMX already ends up running with EFER.NXE=1 on old processors that lack the
"load EFER" controls, because it may help avoiding a slow MSR write. Removing
all the conditionals simplifies the code.
SVM does not have similar code, but it should since recent AMD processors do
support SMEP. So this patch also makes the code for the two vendors more similar
while fixing NPT=0, CR0.WP=1 and CR4.SMEP=1 on AMD processors.
[tyhicks: Backport to 4.15
- vmx.c is up one directory level] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Mon, 30 Sep 2019 16:48:44 +0000 (18:48 +0200)]
kvm: x86, powerpc: do not allow clearing largepages debugfs entry
The largepages debugfs entry is incremented/decremented as shadow
pages are created or destroyed. Clearing it will result in an
underflow, which is harmless to KVM but ugly (and could be
misinterpreted by tools that use debugfs information), so make
this particular statistic read-only.
Cc: kvm-ppc@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(backported from commit 833b45de69a6016c4b0cebe6765d526a31a81580)
[tyhicks: Backport to 4.15
- largepages_* are not present in the debugfs_entries list in book3s.c
- VM_STAT() does not exist in book3s.c
- Calls to debugfs_create_file() are error checked] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Sun, 30 Jun 2019 12:36:21 +0000 (08:36 -0400)]
KVM: x86: change kvm_mmu_page_get_gfn BUG_ON to WARN_ON
Note that in such a case it is quite likely that KVM will BUG_ON
in __pte_list_remove when the VM is closed. However, there is no
immediate risk of memory corruption in the host so a WARN_ON is
enough and it lets you gather traces for debugging.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(cherry picked from commit e9f2a760b158551bfbef6db31d2cae45ab8072e5) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Sun, 23 Jun 2019 17:15:49 +0000 (19:15 +0200)]
KVM: x86: remove now unneeded hugepage gfn adjustment
After the previous patch, the low bits of the gfn are masked in
both FNAME(fetch) and __direct_map, so we do not need to clear them
in transparent_hugepage_adjust.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(cherry picked from commit d679b32611c0102ce33b9e1a4e4b94854ed1812a) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Paolo Bonzini [Mon, 24 Jun 2019 11:06:21 +0000 (13:06 +0200)]
KVM: x86: make FNAME(fetch) and __direct_map more similar
These two functions are basically doing the same thing through
kvm_mmu_get_page, link_shadow_page and mmu_set_spte; yet, for historical
reasons, their code looks very different. This patch tries to take the
best of each and make them very similar, so that it is easy to understand
changes that apply to both of them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(backported from commit 3fcf2d1bdeb6a513523cb2c77012a6b047aa859c)
[tyhicks: Backport to 4.15
- Minor context change due to mmu not being a pointer in the
kvm_vcpu_arch struct] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Junaid Shahid [Fri, 4 Jan 2019 00:22:21 +0000 (16:22 -0800)]
kvm: x86: Do not release the page inside mmu_set_spte()
Release the page at the call-site where it was originally acquired.
This makes the exit code cleaner for most call sites, since they
do not need to duplicate code between success and the failure
label.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(cherry picked from commit 43fdcda96e2550c6d1c46fb8a78801aa2f7276ed) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Junaid Shahid [Fri, 4 Jan 2019 01:14:28 +0000 (17:14 -0800)]
kvm: Convert kvm_lock to a mutex
It doesn't seem as if there is any particular need for kvm_lock to be a
spinlock, so convert the lock to a mutex so that sleepable functions (in
particular cond_resched()) can be called while holding it.
Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
CVE-2018-12207
(backported from commit 0d9ce162cf46c99628cc5da9510b959c7976735b)
[tyhicks: Backport to 4.15
- kvm_hyperv_tsc_notifier() does not exist] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Tyler Hicks [Wed, 30 Oct 2019 03:28:46 +0000 (03:28 +0000)]
UBUNTU: [Config] Disable TSX by default when possible
Turn on CONFIG_X86_INTEL_TSX_MODE_OFF to disable Intel's Transactional
Synchronization Extensions (TSX) feature by default. TSX can only be
disable on certain, newer processors that support the IA32_TSX_CTRL MSR
via a microcode update. Intel says that future processors will also
support the MSR. On processors that support the MSR, TSX will be
disabled unless the system administrator overrides the configuration
with the "tsx" kernel command line option.
CVE-2019-11135
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Tyler Hicks [Tue, 29 Oct 2019 21:58:08 +0000 (21:58 +0000)]
UBUNTU: SAUCE: x86/cpu: Include cpu header from bugs.c
The linux-4.14.y backport of commit 286836a70433 ("x86/cpu: Add a helper
function x86_read_arch_cap_msr()") added a dependency on cpu.h from
bugs.c so include the header file from bugs.c
The linux-4.14.y backport of upstream commit 95c5824f75f3 ("x86/cpu: Add
a "tsx=" cmdline option with TSX disabled by default") incorrectly
dropped the call to tsx_init(). Add the function call back to
identify_boot_cpu()
There is a general consensus that TSX usage is not largely spread while
the history shows there is a non trivial space for side channel attacks
possible. Therefore the tsx is disabled by default even on platforms
that might have a safe implementation of TSX according to the current
knowledge. This is a fair trade off to make.
There are, however, workloads that really do benefit from using TSX and
updating to a newer kernel with TSX disabled might introduce a
noticeable regressions. This would be especially a problem for Linux
distributions which will provide TAA mitigations.
Introduce config options X86_INTEL_TSX_MODE_OFF, X86_INTEL_TSX_MODE_ON
and X86_INTEL_TSX_MODE_AUTO to control the TSX feature. The config
setting can be overridden by the tsx cmdline options.
Add the documenation for TSX Async Abort. Include the description of
the issue, how to check the mitigation state, control the mitigation,
guidance for system administrators.
[ bp: Add proper SPDX tags, touch ups by Josh and me. ]
Co-developed-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
CVE-2019-11135
Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Platforms which are not affected by X86_BUG_TAA may want the TSX feature
enabled. Add "auto" option to the TSX cmdline parameter. When tsx=auto
disable TSX when X86_BUG_TAA is present, otherwise enable TSX.
More details on X86_BUG_TAA can be found here:
https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html
[ bp: Extend the arg buffer to accommodate "auto\0". ]
projects / mirror_ubuntu-bionic-kernel.git / log