Doing this allows using registers as retrieved from an mcontext to be
pushed to a process using PTRACE_SETREGS.
It is not entirely clear to me why CSGSFS was masked. Doing so creates
issues when using the mcontext as process state in seccomp and simply
copying the register appears to work perfectly fine for ptrace.
Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Link: https://patch.msgid.link/20250224181827.647129-2-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Minimum version of binutils required to compile the kernel is 2.25.
This version correctly handles the "lock" prefix, so it is possible
to remove the semicolon, which was used to support ancient versions
of GNU as.
Due to the semicolon, the compiler considers "lock; insn" as two
separate instructions. Removing the semicolon makes asm length
calculations more accurate, consequently making scheduling and
inlining decisions of the compiler more accurate.
Removing the semicolon also enables assembler checks involving lock
prefix. Trying to assemble e.g. "lock andl %eax, %ebx" results in:
Error: expecting lockable instruction after `lock'
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://patch.msgid.link/20250228090058.2499163-1-ubizjak@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of dynamically allocating the pointer to the vdso page during
boot, we can just allocate it statically. Doing so will reduce error
handling and make the code slightly more readable.
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Link: https://patch.msgid.link/20250212045756.164977-1-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Mark read-only data actually read-only (simple mprotect), and
to be able to test it also implement _nofault accesses. This
works by setting up a new "segv_continue" pointer in current,
and then when we hit a segfault we change the signal return
context so that we continue at that address. The code using
this sets it up so that it jumps to a label and then aborts
the access that way, returning -EFAULT.
It's possible to optimize the ___backtrack_faulted() thing by
using asm goto (compiler version dependent) and/or gcc's (not
sure if clang has it) &&label extension, but at least in one
attempt I made the && caused the compiler to not load -EFAULT
into the register in case of jumping to the &&label from the
fault handler. So leave it like this for now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Co-developed-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20250210160926.420133-2-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The stack needs to be properly aligned so 16 byte memory accesses on the
stack are correct. This was broken when introducing the dynamic math
register sizing as the rounding was not moved appropriately.
Fixes: 3f17fed21491 ("um: switch to regset API and depend on XSTATE")
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20250107133509.265576-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
It was reported that qemu may not enable the XSTATE CPU extension, which
is a requirement after commit 3f17fed21491 ("um: switch to regset API
and depend on XSTATE"). Add a fallback to use FXSAVE (FP registers on
x86_64 and XFP on i386) which is just a shorter version of the same
data. The only difference is that the XSTATE magic should not be set in
the signal frame.
Note that this still drops support for the older i386 FP register layout
as supporting this would require more backward compatibility to build a
correct signal frame.
Fixes: 3f17fed21491 ("um: switch to regset API and depend on XSTATE")
Reported-by: SeongJae Park <sj@kernel.org>
Closes: https://lore.kernel.org/r/20241203070218.240797-1-sj@kernel.org
Tested-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20241204074827.1582917-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This header is no longer used after the removal of fixmap support
in commit 5bfc4a3a0af3 ("um: Remove obsolete fixmap support").
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Link: https://patch.msgid.link/20250113153218.3331321-3-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
sparse reports that various places were missing the __user tag in casts.
In addition, one location was using 0 instead of NULL.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20241031142017.430420-2-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The PTRACE_GETREGSET API has now existed since Linux 2.6.33. The XSAVE
CPU feature should also be sufficiently common to be able to rely on it.
With this, define our internal FP state to be the hosts XSAVE data. Add
discovery for the hosts XSAVE size and place the FP registers at the end
of task_struct so that we can adjust the size at runtime.
Next we can implement the regset API on top and update the signal
handling as well as ptrace APIs to use them. Also switch coredump
creation to use the regset API and finally set HAVE_ARCH_TRACEHOOK.
This considerably improves the signal frames. Previously they might not
have contained all the registers (i386) and also did not have the
sizes and magic values set to the correct values to permit userspace to
decode the frame.
As a side effect, this will permit UML to run on hosts with newer CPU
extensions (such as AMX) that need even more register state.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20241023094120.4083426-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of using a custom script to detect and fail on undefined
references, use --no-undefined for all VDSO linker invocations.
Drop the now unused checkundef.sh script.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20241011-vdso-checkundef-v1-2-1a46e0352d20@linutronix.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since __attribute__((naked)) cannot be used with functions
containing C statements, just generate the few instructions
it needs in assembly directly.
While at it, fix the stack usage ("1 + 2*x - 1" is odd) and
document what it must do, and why it must adjust the stack.
Fixes: 8508a5e0e9db ("um: Fix misaligned stack in stub_exe")
Link: https://lore.kernel.org/linux-um/CABVgOSntH-uoOFMP5HwMXjx_f1osMnVdhgKRKm4uz6DFm2Lb8Q@mail.gmail.com/
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The larger memory space is useful to support more applications inside
UML. One example for this is ASAN instrumentation of userspace
applications which requires addresses that would otherwise not be
available.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240919124511.282088-11-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When loading the UML binary, the host kernel will place the stack at the
highest possible address. It will then map the program name and
environment variables onto the start of the stack.
As such, an easy way to figure out the host_task_size is to use the
highest pointer to an environment variable as a reference.
Ensure that this works by disabling address layout randomization and
re-executing UML in case it was enabled.
This increases the available TASK_SIZE for 64 bit UML considerably.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240919124511.282088-9-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of using the current stack pointer, we can also use the current
instruction to calculate where the stub data is. With this the stub data
only needs to be aligned to a full page boundary.
Changing this has the advantage that we do not have a hole in the memory
space above the stub data (which would need to be explicitly cleared).
Another motivation to do this is that with the planned addition of a
SECCOMP based userspace the stack pointer may not be fully trustworthy.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240919124511.282088-7-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The 64bit version did not have a stub_syscall1 function yet. Add it as
it will be useful to implement a static binary for stub loading.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240919124511.282088-2-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The highmem support has been removed by commit a98a6d864d3b ("um:
Remove broken highmem support"). The 2-level page table is sufficient
on UML/i386 now. Remove the 3-level page table support on UML/i386
which is still marked as experimental.
Suggested-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Link: https://patch.msgid.link/20240918061702.614837-1-tiwei.btw@antgroup.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When switching from userspace to the kernel, all registers including the
FP registers are copied into the kernel and restored later on. As such,
the true source for the FP register state is actually already in the
kernel and they should never be grabbed from the userspace process.
Change the various places to simply copy the data from the internal FP
register storage area. Note that on i386 the format of PTRACE_GETFPREGS
and PTRACE_GETFPXREGS is different enough that conversion would be
needed. With this patch, -EINVAL is returned if the non-native format is
requested.
The upside is, that this patchset fixes setting registers via ptrace
(which simply did not work before) as well as fixing setting floating
point registers using the mcontext on signal return on i386.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240913133845.964292-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The x86 port of UM has efficient unaligned access. Set the option as it
is appropriate and will e.g. cause UBSAN to not enable unaligned memory
access checking by default.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240913134442.967599-6-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This header no longer serves a purpose after show_trace was removed
by commit 9d1ee8ce92e1 ("um: Rewrite show_stack()").
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
All relevant architectures had already been converted to the new interface
(which just has an underscore in front of the name - not very imaginative
naming), this just force-converts the stragglers.
The modern interface is almost identical to the old one, except instead of
the page pointer it takes a "struct vm_special_mapping" that describes the
mapping (and contains the page pointer as one member), and it returns the
resulting 'vma' instead of just the error code.
Getting rid of the old interface also gets rid of some special casing,
which had caused problems with the mremap extensions to "struct
vm_special_mapping".
[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/CAHk-=whvR+z=0=0gzgdfUiK70JTa-=+9vxD-4T=3BagXR6dciA@mail.gmail.comTested-by: Rob Landley <rob@landley.net> # arch/sh/
Link: https://lore.kernel.org/all/20240819195120.GA1113263@thelio-3990X/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Jeff Xu <jeffxu@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Landley <rob@landley.net>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- Support for preemption
- i386 Rust support
- Huge cleanup by Benjamin Berg
- UBSAN support
- Removal of dead code
-----BEGIN PGP SIGNATURE-----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=ybqq
-----END PGP SIGNATURE-----
Merge tag 'uml-for-linus-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux
Pull UML updates from Richard Weinberger:
- Support for preemption
- i386 Rust support
- Huge cleanup by Benjamin Berg
- UBSAN support
- Removal of dead code
* tag 'uml-for-linus-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: (41 commits)
um: vector: always reset vp->opened
um: vector: remove vp->lock
um: register power-off handler
um: line: always fill *error_out in setup_one_line()
um: remove pcap driver from documentation
um: Enable preemption in UML
um: refactor TLB update handling
um: simplify and consolidate TLB updates
um: remove force_flush_all from fork_handler
um: Do not flush MM in flush_thread
um: Delay flushing syscalls until the thread is restarted
um: remove copy_context_skas0
um: remove LDT support
um: compress memory related stub syscalls while adding them
um: Rework syscall handling
um: Add generic stub_syscall6 function
um: Create signal stack memory assignment in stub_data
um: Remove stub-data.h include from common-offsets.h
um: time-travel: fix signal blocking race/hang
um: time-travel: remove time_exit()
...
Since userspace state is saved in the MM process, kernel using
FPU still doesn't really need to do anything, so this really
is as simple as enabling preemption. The irq critical section
in sigio_handler() needs preempt_disable()/preempt_enable().
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://patch.msgid.link/20240702102549.d2fcea450854.I12f5a53d80ec1e425e66ef272b1e95cb523b608e@changeid
[rebase, remove FPU save/restore, fix x86/um Makefile,
rewrite commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The kernel flushes the memory ranges anyway for CoW and does not assume
that the userspace process has anything set up already. So, start with a
fresh process for the new mm context.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240703134536.1161108-8-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The current LDT code has a few issues that mean it should be redone in a
different way once we always start with a fresh MM even when cloning.
In a new and better world, the kernel would just ensure its own LDT is
clear at startup. At that point, all that is needed is a simple function
to populate the LDT from another MM in arch_dup_mmap combined with some
tracking of the installed LDT entries for each MM.
Note that the old implementation was even incorrect with regard to
reading, as it copied out the LDT entries in the internal format rather
than converting them to the userspace structure.
Removal should be fine as the LDT is not used for thread-local storage
anymore.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://patch.msgid.link/20240703134536.1161108-7-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Rework syscall handling to be platform independent. Also create a clean
split between queueing of syscalls and flushing them out, removing the
need to keep state in the code that triggers the syscalls.
The code adds syscall_data_len to the global mm_id structure. This will
be used later to allow surrounding code to track whether syscalls still
need to run and if errors occurred.
Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Link: https://patch.msgid.link/20240703134536.1161108-5-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Further commits will require values from common-offsets.h inside
stub-data.h. Resolve the possible circular dependency and simply use
offsetof() inside stub_32.h and stub_64.h.
Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Link: https://patch.msgid.link/20240703134536.1161108-2-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The direct-call syscall dispatch function doesn't know that the exit()
and exit_group() syscall handlers don't return, so the call sites aren't
optimized accordingly.
Fix that by marking the exit syscall declarations __noreturn.
Fixes the following warnings:
vmlinux.o: warning: objtool: x64_sys_call+0x2804: __x64_sys_exit() is missing a __noreturn annotation
vmlinux.o: warning: objtool: ia32_sys_call+0x29b6: __ia32_sys_exit_group() is missing a __noreturn annotation
Fixes: 1e3ad78334a6 ("x86/syscall: Don't force use of indirect calls for system calls")
Closes: https://lkml.kernel.org/lkml/6dba9b32-db2c-4e6d-9500-7a08852f17a3@paulmck-laptop
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/5d8882bc077d8eadcc7fd1740b56dfb781f12288.1719381528.git.jpoimboe@kernel.org
- Fixes for -Wmissing-prototypes warnings and further cleanup
- Remove callback returning void from rtc and virtio drivers
- Fix bash location
-----BEGIN PGP SIGNATURE-----
iQJKBAABCAA0FiEEdgfidid8lnn52cLTZvlZhesYu8EFAmZQ/FYWHHJpY2hhcmRA
c2lnbWEtc3Rhci5hdAAKCRBm+VmF6xi7wfbLEAC1X55jjignxMIt4gEbtOXL2Pgn
Md3z8sr5QhyQeLEkoYEhAqYHcKYY8A9ZshfNS4RNTbhU6qaFQBNwbBuFnJ1MsllC
236EKgy0xFChgqH0bszGW97VRcIs79qauDt0mE0AXQGpuW7AjJX9chT2ikp9Sr5z
P2Gnp7+l/OaAH7UXFpaYYOWOzRAQCbA67hN3nRcSBCPq+Plw2bQCCKKK0g4UwqmI
vukAguO3eGZ0B4oQEsPX/krM0IigM01l5pJVhkdNzJgMOfd7eWb3o3juE35f4KPx
vSd8LPmoBvDJt9dKbZE38fC58+U9qWDcBDLfDlf7F0dGtWQi6QeZmrmQSteQUAFF
YWHllQ+P6xdh1kdSXWk8IesVINydMAc79DpqmKkEUgmCGVX+grt40aOTnOIUuzjq
9lMcfKgjjBz6qsC3fWyGMvjaPpRRbe4G1wnAOij+hdBNR2fEFaqv8Dx9Zx42G3lm
oYDylqjP73SbtOKbTCdHTqOfTSC83KYmo6w5ttwnFZcDVtbXRY8NejIX08Go8KIn
OXeZ8Pxf3DmQ4yuhE3mWOoT/eFiZnXpoNiteQZ/8RhyPMJllVijtSIlnLteuah4d
Z68Nh9/P52VcjMH0wS1eTKrkUAgfGBQ3kIOZqbU8UMSeq8vTB2kx++HwAtmUNi07
pDaNOQVtW5m4HMhVlw==
=umlG
-----END PGP SIGNATURE-----
Merge tag 'uml-for-linus-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux
Pull UML updates from Richard Weinberger:
- Fixes for -Wmissing-prototypes warnings and further cleanup
- Remove callback returning void from rtc and virtio drivers
- Fix bash location
* tag 'uml-for-linus-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: (26 commits)
um: virtio_uml: Convert to platform remove callback returning void
um: rtc: Convert to platform remove callback returning void
um: Remove unused do_get_thread_area function
um: Fix -Wmissing-prototypes warnings for __vdso_*
um: Add an internal header shared among the user code
um: Fix the declaration of kasan_map_memory
um: Fix the -Wmissing-prototypes warning for get_thread_reg
um: Fix the -Wmissing-prototypes warning for __switch_mm
um: Fix -Wmissing-prototypes warnings for (rt_)sigreturn
um: Stop tracking host PID in cpu_tasks
um: process: remove unused 'n' variable
um: vector: remove unused len variable/calculation
um: vector: fix bpfflash parameter evaluation
um: slirp: remove set but unused variable 'pid'
um: signal: move pid variable where needed
um: Makefile: use bash from the environment
um: Add winch to winch_handlers before registering winch IRQ
um: Fix -Wmissing-prototypes warnings for __warp_* and foo
um: Fix -Wmissing-prototypes warnings for text_poke*
um: Move declarations to proper headers
...
Now Kbuild provides reasonable defaults for objtool, sanitizers, and
profilers.
Remove redundant variables.
Note:
This commit changes the coverage for some objects:
- include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV
- include arch/sparc/vdso/vdso-image-*.o into UBSAN
- include arch/sparc/vdso/vma.o into UBSAN
- include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vma.o into GCOV, KCOV
- include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV
I believe these are positive effects because all of them are kernel
space objects.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Roberto Sassu <roberto.sassu@huawei.com>
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:
src := $(obj)
When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.
This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.
To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.
Going forward, the variables used in Makefiles will have the following
meanings:
$(obj) - directory in the object tree
$(src) - directory in the source tree (changed by this commit)
$(objtree) - the top of the kernel object tree
$(srctree) - the top of the kernel source tree
Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
It's not used since it was introduced by commit aa6758d4867c ("[PATCH]
uml: implement {get,set}_thread_area for i386"). Now, it's causing a
-Wmissing-prototypes warning:
arch/x86/um/tls_32.c:39:5: warning: no previous prototype for ‘do_get_thread_area’ [-Wmissing-prototypes]
39 | int do_get_thread_area(struct user_desc *info)
| ^~~~~~~~~~~~~~~~~~
The original author also had doubts about whether it should be used.
Considering that 18 years have passed, let's just remove it.
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
The VDSO functions are defined as globals and intended to be called
from userspace. Let's just workaround the -Wmissing-prototypes warnings
by declaring them locally.
This will address below -Wmissing-prototypes warnings:
arch/x86/um/vdso/um_vdso.c:16:5: warning: no previous prototype for ‘__vdso_clock_gettime’ [-Wmissing-prototypes]
arch/x86/um/vdso/um_vdso.c:30:5: warning: no previous prototype for ‘__vdso_gettimeofday’ [-Wmissing-prototypes]
arch/x86/um/vdso/um_vdso.c:44:21: warning: no previous prototype for ‘__vdso_time’ [-Wmissing-prototypes]
arch/x86/um/vdso/um_vdso.c:57:1: warning: no previous prototype for ‘__vdso_getcpu’ [-Wmissing-prototypes]
While at it, also fix the "WARNING: Prefer 'unsigned int *' to bare
use of 'unsigned *'" checkpatch warning.
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
The get_thread_reg function is defined in the user code, and is
called by the kernel code. It should be declared in a shared header.
Fixes: dbba7f704aa0 ("um: stop polluting the namespace with registers.h contents")
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Use SYSCALL_DEFINE0 to define (rt_)sigreturn. This will address
below -Wmissing-prototypes warnings:
arch/x86/um/signal.c:453:6: warning: no previous prototype for ‘sys_sigreturn’ [-Wmissing-prototypes]
arch/x86/um/signal.c:560:6: warning: no previous prototype for ‘sys_rt_sigreturn’ [-Wmissing-prototypes]
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
We have W=1 warnings on 64-bit because the pid is only
used in branches on 32-bit; move it inside to get rid of
the warnings.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
These functions are not called explicitly. Let's just workaround
the -Wmissing-prototypes warnings by declaring them locally similar
to what was done in arch/x86/kernel/asm-offsets_32.c.
This will address below -Wmissing-prototypes warnings:
./arch/x86/um/shared/sysdep/kernel-offsets.h:9:6: warning: no previous prototype for ‘foo’ [-Wmissing-prototypes]
arch/um/os-Linux/main.c:187:7: warning: no previous prototype for ‘__wrap_malloc’ [-Wmissing-prototypes]
arch/um/os-Linux/main.c:208:7: warning: no previous prototype for ‘__wrap_calloc’ [-Wmissing-prototypes]
arch/um/os-Linux/main.c:222:6: warning: no previous prototype for ‘__wrap_free’ [-Wmissing-prototypes]
arch/x86/um/user-offsets.c:17:6: warning: no previous prototype for ‘foo’ [-Wmissing-prototypes]
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This will address below -Wmissing-prototypes warnings:
arch/um/kernel/initrd.c:18:12: warning: no previous prototype for ‘read_initrd’ [-Wmissing-prototypes]
arch/um/kernel/um_arch.c:408:19: warning: no previous prototype for ‘read_initrd’ [-Wmissing-prototypes]
arch/um/os-Linux/start_up.c:301:12: warning: no previous prototype for ‘parse_iomem’ [-Wmissing-prototypes]
arch/x86/um/ptrace_32.c:15:6: warning: no previous prototype for ‘arch_switch_to’ [-Wmissing-prototypes]
arch/x86/um/ptrace_32.c:101:5: warning: no previous prototype for ‘poke_user’ [-Wmissing-prototypes]
arch/x86/um/ptrace_32.c:153:5: warning: no previous prototype for ‘peek_user’ [-Wmissing-prototypes]
arch/x86/um/ptrace_64.c:111:5: warning: no previous prototype for ‘poke_user’ [-Wmissing-prototypes]
arch/x86/um/ptrace_64.c:171:5: warning: no previous prototype for ‘peek_user’ [-Wmissing-prototypes]
arch/x86/um/syscalls_64.c:48:6: warning: no previous prototype for ‘arch_switch_to’ [-Wmissing-prototypes]
arch/x86/um/tls_32.c:184:5: warning: no previous prototype for ‘arch_switch_tls’ [-Wmissing-prototypes]
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This will address below -Wmissing-prototypes warnings:
arch/um/kernel/mem.c:202:8: warning: no previous prototype for ‘pgd_alloc’ [-Wmissing-prototypes]
arch/um/kernel/mem.c:215:7: warning: no previous prototype for ‘uml_kmalloc’ [-Wmissing-prototypes]
arch/um/kernel/process.c:207:6: warning: no previous prototype for ‘arch_cpu_idle’ [-Wmissing-prototypes]
arch/um/kernel/process.c:328:15: warning: no previous prototype for ‘arch_align_stack’ [-Wmissing-prototypes]
arch/um/kernel/reboot.c:45:6: warning: no previous prototype for ‘machine_restart’ [-Wmissing-prototypes]
arch/um/kernel/reboot.c:51:6: warning: no previous prototype for ‘machine_power_off’ [-Wmissing-prototypes]
arch/um/kernel/reboot.c:57:6: warning: no previous prototype for ‘machine_halt’ [-Wmissing-prototypes]
arch/um/kernel/skas/mmu.c:17:5: warning: no previous prototype for ‘init_new_context’ [-Wmissing-prototypes]
arch/um/kernel/skas/mmu.c:60:6: warning: no previous prototype for ‘destroy_context’ [-Wmissing-prototypes]
arch/um/kernel/skas/process.c:36:12: warning: no previous prototype for ‘start_uml’ [-Wmissing-prototypes]
arch/um/kernel/time.c:807:15: warning: no previous prototype for ‘calibrate_delay_is_known’ [-Wmissing-prototypes]
arch/um/kernel/tlb.c:594:6: warning: no previous prototype for ‘force_flush_all’ [-Wmissing-prototypes]
arch/x86/um/bugs_32.c:22:6: warning: no previous prototype for ‘arch_check_bugs’ [-Wmissing-prototypes]
arch/x86/um/bugs_32.c:44:6: warning: no previous prototype for ‘arch_examine_signal’ [-Wmissing-prototypes]
arch/x86/um/bugs_64.c:9:6: warning: no previous prototype for ‘arch_check_bugs’ [-Wmissing-prototypes]
arch/x86/um/bugs_64.c:13:6: warning: no previous prototype for ‘arch_examine_signal’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:10:12: warning: no previous prototype for ‘elf_core_extra_phdrs’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:15:5: warning: no previous prototype for ‘elf_core_write_extra_phdrs’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:42:5: warning: no previous prototype for ‘elf_core_write_extra_data’ [-Wmissing-prototypes]
arch/x86/um/elfcore.c:63:8: warning: no previous prototype for ‘elf_core_extra_data_size’ [-Wmissing-prototypes]
arch/x86/um/fault.c:18:5: warning: no previous prototype for ‘arch_fixup’ [-Wmissing-prototypes]
arch/x86/um/os-Linux/mcontext.c:7:6: warning: no previous prototype for ‘get_regs_from_mc’ [-Wmissing-prototypes]
arch/x86/um/os-Linux/tls.c:22:6: warning: no previous prototype for ‘check_host_supports_tls’ [-Wmissing-prototypes]
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This will also fix the warnings like:
warning: no previous prototype for ‘fork_handler’ [-Wmissing-prototypes]
140 | void fork_handler(void)
| ^~~~~~~~~~~~
Signed-off-by: Tiwei Bie <tiwei.btw@antgroup.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
- Clang coverage support
- Many cleanups from Benjamin Berg
- Various minor fixes
-----BEGIN PGP SIGNATURE-----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=oH6k
-----END PGP SIGNATURE-----
Merge tag 'uml-for-linus-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux
Pull UML updates from Richard Weinberger:
- Clang coverage support
- Many cleanups from Benjamin Berg
- Various minor fixes
* tag 'uml-for-linus-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
um: Mark 32bit syscall helpers as clobbering memory
um: Remove unused register save/restore functions
um: Rely on PTRACE_SETREGSET to set FS/GS base registers
Documentation: kunit: Add clang UML coverage example
arch: um: Add Clang coverage support
um: time-travel: fix time corruption
um: net: Fix return type of uml_net_start_xmit()
um: Always inline stub functions
um: Do not use printk in userspace trampoline
um: Reap winch thread if it fails
um: Do not use printk in SIGWINCH helper thread
um: Don't use vfprintf() for os_info()
um: Make errors to stop ptraced child fatal during startup
um: Drop NULL check from start_userspace
um: Drop support for hosts without SYSEMU_SINGLESTEP support
um: document arch_futex_atomic_op_inuser
um: mmu: remove stub_pages
um: Fix naming clash between UML and scheduler
um: virt-pci: fix platform map offset
The 64bit helper are marked to clobber the memory, but the 32bit ones
are not. Add the appropriate clobber to the 32bit helper routines so
that the compiler cannot do invalid optimizations.
Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
These registers are saved/restored together with the other general
registers using ptrace. In arch_set_tls we then just need to set the
register and it will be synced back normally.
Most of this logic was introduced in commit f355559cf7845 ("[PATCH] uml:
x86_64 thread fixes"). However, at least today we can rely on ptrace to
restore the base registers for us. As such, only the part of the patch
that tracks the FS register for use as thread local storage is actually
needed.
Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
The stub executable page is remapped to a different location in the
userland process. As these functions may be used by the stub, they
really need to be always inlined rather than permitting the compiler to
emit a function.
Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
These features have existed since Linux 2.6.14 and can be considered
widely available at this point. Also drop the backward compatibility
code for PTRACE_SETOPTIONS.
Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
----
v2:
* Continue to define PTRACE_SYSEMU_SINGLESTEP as glibc only added it in
version 2.27.
Signed-off-by: Richard Weinberger <richard@nod.at>
This is needed for killing the sched.h dependency on rcupdate.h, and
pid.h is a better place for this code anyways.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
