linux-stable.git/arch/um/kernel/process.c, branch linux-5.4.y

um: Fix the return value of elf_core_copy_task_fpregs

2024-12-14T18:44:39+00:00

[ Upstream commit 865e3845eeaa21e9a62abc1361644e67124f1ec0 ]

This function is expected to return a boolean value, which should be
true on success and false on failure.

Fixes: d1254b12c93e ("uml: fix x86_64 core dump crash")
Signed-off-by: Tiwei Bie 
Link: https://patch.msgid.link/20240913023302.130300-1-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

um: Fix naming clash between UML and scheduler

2024-02-23T07:25:02+00:00

[ Upstream commit 541d4e4d435c8b9bfd29f70a1da4a2db97794e0a ]

__cant_sleep was already used and exported by the scheduler.
The name had to be changed to a UML specific one.

Signed-off-by: Anton Ivanov 
Reviewed-by: Peter Lafreniere 
Signed-off-by: Richard Weinberger 
Signed-off-by: Sasha Levin

ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP

2022-06-14T16:11:24+00:00

commit c200e4bb44e80b343c09841e7caaaca0aac5e5fa upstream.

User mode linux is the last user of the PT_DTRACE flag.  Using the flag to indicate
single stepping is a little confusing and worse changing tsk->ptrace without locking
could potentionally cause problems.

So use a thread info flag with a better name instead of flag in tsk->ptrace.

Remove the definition PT_DTRACE as uml is the last user.

Cc: stable@vger.kernel.org
Acked-by: Johannes Berg 
Tested-by: Kees Cook 
Reviewed-by: Oleg Nesterov 
Link: https://lkml.kernel.org/r/20220505182645.497868-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" 
Signed-off-by: Greg Kroah-Hartman

um: Implement copy_thread_tls

2020-01-14T19:08:35+00:00

commit 457677c70c7672a4586b0b8abc396cc1ecdd376d upstream.

This is required for clone3 which passes the TLS value through a
struct rather than a register.

Signed-off-by: Amanieu d'Antras 
Cc: linux-um@lists.infradead.org
Cc:  # 5.3.x
Link: https://lore.kernel.org/r/20200104123928.1048822-1-amanieu@gmail.com
Signed-off-by: Christian Brauner 
Signed-off-by: Greg Kroah-Hartman

um: Add SPDX headers to files in arch/um/kernel/

2019-09-15T19:37:17+00:00

Convert files to use SPDX header. All files are licensed under the
GPLv2.

Signed-off-by: Alex Dewar 
Signed-off-by: Richard Weinberger

um: time-travel: Restrict time update in IRQ handler

2019-09-15T19:37:13+00:00

We currently do the time updates in the timer handler, even if
we just call the timer handler ourselves. In basic mode we must
in fact do it there since otherwise the OS timer signal won't
move time forward, but in inf-cpu mode we don't need to, and
it's harder to understand.

Restrict the update there to basic mode, adding a comment, and
do it before calling the timer_handler() in inf-cpu mode.

Signed-off-by: Johannes Berg 
Signed-off-by: Richard Weinberger

um: time-travel: Fix periodic timers

2019-09-15T19:37:13+00:00

Periodic timers are broken, because the also only fire once.
As it happens, Linux doesn't care because it only sets the
timer to periodic very briefly during boot, and then switches
it only between one-shot and off later.

Nevertheless, fix the logic (we shouldn't even be looking at
time_travel_timer_expiry unless the timer is enabled) and
change the code to fire the timer periodically in periodic
mode, in case it ever gets used in the future.

Signed-off-by: Johannes Berg 
Signed-off-by: Richard Weinberger

um: fix time travel mode

2019-08-22T22:39:53+00:00

Unfortunately, my build fix for when time travel mode isn't
enabled broke time travel mode, because I forgot that we need
to use the timer time after the timer has been marked disabled,
and thus need to leave the time stored instead of zeroing it.

Fix that by splitting the inline into two, so we can call only
the _mode() one in the relevant code path.

Fixes: b482e48d29f1 ("um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT")
Signed-off-by: Johannes Berg 
Signed-off-by: Richard Weinberger

um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT

2019-07-04T07:52:18+00:00

When CONFIG_UML_TIME_TRAVEL_SUPPORT isn't set, the build was broken.
Fix this.

Fixes: 065038706f77 ("um: Support time travel mode")
Signed-off-by: Johannes Berg 
Signed-off-by: Richard Weinberger

um: Support time travel mode

2019-07-02T21:27:36+00:00

Sometimes it can be useful to run with "time travel" inside the
UML instance, for example for testing. For example, some tests
for the wireless subsystem and userspace are based on hwsim, a
virtual wireless adapter. Some tests can take a long time to
run because they e.g. wait for 120 seconds to elapse for some
regulatory checks. This obviously goes faster if it need not
actually wait that long, but time inside the test environment
just "bumps up" when there's nothing to do.

Add CONFIG_UML_TIME_TRAVEL_SUPPORT to enable code to support
such modes at runtime, selected on the command line:
 * just "time-travel", in which time inside the UML instance
   can move faster than real time, if there's nothing to do
 * "time-travel=inf-cpu" in which time also moves slower and
   any CPU processing takes no time at all, which allows to
   implement consistent behaviour regardless of host CPU load
   (or speed) or debug overhead.

An additional "time-travel-start=" parameter is also
supported in this case to start the wall clock at this time
(in unix epoch).

With this enabled, the test mentioned above goes from a runtime
of about 140 seconds (with startup overhead and all) to being
CPU bound and finishing in 15 seconds (on my slow laptop).

Signed-off-by: Johannes Berg 
Signed-off-by: Richard Weinberger