linux-toradex.git/arch/um/os-Linux, branch v5.10-rc2

um: Fix incorrect assumptions about max pid length

2020-10-11T21:21:06+00:00

pids are no longer limited to 16-bits, bump to 32-bits,
ie. 9 decimal characters.  Additionally sizeof("/") already
returns 2 - ie. it already accounts for trailing zero.

Cc: Jeff Dike 
Cc: Richard Weinberger 
Cc: Anton Ivanov 
Cc: Linux UM Mailing List 
Signed-off-by: Maciej Żenczykowski 
Signed-off-by: Richard Weinberger

um: Some fixes to build UML with musl

2020-10-11T21:13:06+00:00

musl toolchain and headers are a bit more strict. These fixes enable building
UML with musl as well as seem not to break on glibc.

Signed-off-by: Ignat Korchagin 
Tested-by: Brendan Higgins 
Signed-off-by: Richard Weinberger

um: Use fdatasync() when mapping the UBD FSYNC command

2020-06-02T20:37:55+00:00

We do not need to update the metadata (atime, mtime, etc)
on the UBD file and/or the COW file until UML exits.

UBD image mtime is checked in UML only when opening
the files. After that they are locked and used
exclusively by a single UML instance, so there is
no point wasting resources on updating metadata on
every sync. We can sync data only. The host will
always update mtime if a file has been modified upon
closing it.

Signed-off-by: Anton Ivanov 
Signed-off-by: Richard Weinberger

um: Add include: memset() and memcpy() are in

2020-06-02T20:37:11+00:00

These two functions are otherwise unknown to the pedantic compiler.
Include the correct header to enable the build to succeed.

Signed-off-by: Zach van Rijn 
Acked-By: Anton Ivanov 
Signed-off-by: Richard Weinberger

um: Implement time-travel=ext

2020-03-29T21:29:08+00:00

This implements synchronized time-travel mode which - using a special
application on a unix socket - lets multiple machines take part in a
time-travelling simulation together.

The protocol for the unix domain socket is defined in the new file
include/uapi/linux/um_timetravel.h.

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

um: Move timer-internal.h to non-shared

2020-03-29T21:28:43+00:00

This file isn't really shared, it's only used on the kernel side,
not on the user side. Remove the include from the user-side and
move the file to a better place.

While at it, rename it to time-internal.h, it's not really just
timers but all kinds of things related to timekeeping.

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

um: falloc.h needs to be directly included for older libc

2020-03-29T21:21:42+00:00

When building UML with glibc 2.17 installed, compilation
of arch/um/os-Linux/file.c fails due to failure to find
FALLOC_FL_PUNCH_HOLE and FALLOC_FL_KEEP_SIZE definitions.

It appears that /usr/include/bits/fcntl-linux.h (indirectly
included by /usr/include/fcntl.h) does not include falloc.h
with an older glibc, whereas a more up-to-date version
does.

Adding the direct include to file.c resolves the issue
and does not cause problems for more recent glibc.

Fixes: 50109b5a03b4 ("um: Add support for DISCARD in the UBD Driver")
Cc: Brendan Higgins 
Signed-off-by: Alan Maguire 
Reviewed-by: Brendan Higgins 
Acked-By: Anton Ivanov 
Signed-off-by: Richard Weinberger

um: Fix len of file in create_pid_file

2020-03-29T21:20:07+00:00

sizeof gives us the size of the pointer variable, not of the
area it points to. So the number of bytes copied by umid_file_name()
is 8.
We should pass in the correct length of the file buffer.

Signed-off-by: Wen Yang 
Signed-off-by: Richard Weinberger

um: ubd: use 64-bit time_t where possible

2019-12-18T17:07:31+00:00

The ubd code suffers from a possible y2038 overflow on 32-bit
architectures, both for the cow header and the os_file_modtime()
function.

Replace time_t with time64_t to extend the ubd_kern side as much
as possible.

Whether this makes a difference for the user side depends on
the host libc implementation that may use either 32-bit or 64-bit
time_t.

For the cow file format, the header contains an unsigned 32-bit
timestamp, which is good until y2106, passing this through a
'long long' gives us a consistent interpretation between 32-bit
and 64-bit um kernels.

Signed-off-by: Arnd Bergmann

um: Don't trace irqflags during shutdown

2019-11-25T21:42:57+00:00

In the main() code, we eventually enable signals just before
exec() or exit(), in order to to not have signals pending and
delivered *after* the exec().

I've observed SIGSEGV loops at this point, and the reason seems
to be the irqflags tracing; this makes sense as the kernel is
no longer really functional at this point. Since there's really
no reason to use unblock_signals_trace() here (I had just done
a global search & replace), use the plain unblock_signals() in
this case to avoid going into the no longer functional kernel.

Fixes: 0dafcbe128d2 ("um: Implement TRACE_IRQFLAGS_SUPPORT")
Signed-off-by: Johannes Berg 
Signed-off-by: Richard Weinberger