linux-stable.git/arch/um/include/asm/processor-generic.h, branch v6.14

um: switch to regset API and depend on XSTATE

2024-10-23T10:13:16+00:00

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 
Link: https://patch.msgid.link/20241023094120.4083426-1-benjamin@sipsolutions.net
Signed-off-by: Johannes Berg

um: remove fault_catcher infrastructure

2024-10-23T07:52:46+00:00

This was perhaps intended to do _nofault copies, but the
real reason is lost to history. Remove this, it's not
needed, and using longjmp() out of the middle of the
signal handler with all the state it has modified is
not going to be a good idea anyway.

Link: https://patch.msgid.link/20241010224513.901c4d390b3e.Ia74742668b44603c1ca23dd36f90e964e6e7ee55@changeid
Signed-off-by: Johannes Berg

um: Remove unused fields from thread_struct

2024-09-12T18:35:35+00:00

These fields are no longer used since the removal of tt mode.

Signed-off-by: Tiwei Bie 
Signed-off-by: Richard Weinberger

um: Fix the -Wmissing-prototypes warning for get_thread_reg

2024-04-30T12:15:17+00:00

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 
Signed-off-by: Richard Weinberger

um: Drop support for hosts without SYSEMU_SINGLESTEP support

2024-01-04T22:29:11+00:00

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 

----

v2:
 * Continue to define PTRACE_SYSEMU_SINGLESTEP as glibc only added it in
   version 2.27.
Signed-off-by: Richard Weinberger

um: Make the definition of cpu_data more compatible

2023-02-10T20:36:58+00:00

Match the x86 implementation to improve build errors.
Noticed when building allyesconfig.

e.g.
../arch/um/include/asm/processor-generic.h:94:19: error: called object is not a function or function pointer
   94 | #define cpu_data (&boot_cpu_data)
      |                  ~^~~~~~~~~~~~~~~
../drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_topology.c:2157:16: note: in expansion of macro ‘cpu_data’
 2157 |         return cpu_data(first_cpu_of_numa_node).apicid;

Signed-off-by: Peter Foley 
Signed-off-by: Richard Weinberger

kernel: exit: cleanup release_thread()

2022-09-12T04:55:07+00:00

Only x86 has own release_thread(), introduce a new weak release_thread()
function to clean empty definitions in other ARCHs.

Link: https://lkml.kernel.org/r/20220819014406.32266-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang 
Acked-by: Guo Ren 				[csky]
Acked-by: Russell King (Oracle) 
Acked-by: Geert Uytterhoeven 
Acked-by: Brian Cain 
Acked-by: Michael Ellerman 			[powerpc]
Acked-by: Stafford Horne 			[openrisc]
Acked-by: Catalin Marinas 		[arm64]
Acked-by: Huacai Chen 			[LoongArch]
Cc: Alexander Gordeev 
Cc: Anton Ivanov 
Cc: Borislav Petkov 
Cc: Christian Borntraeger 
Cc: Christophe Leroy 
Cc: Chris Zankel 
Cc: Dave Hansen 
Cc: "David S. Miller" 
Cc: Dinh Nguyen 
Cc: Guo Ren  [csky]
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Ingo Molnar 
Cc: Ivan Kokshaysky 
Cc: James Bottomley 
Cc: Johannes Berg 
Cc: Jonas Bonn 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michal Simek 
Cc: Nicholas Piggin 
Cc: Palmer Dabbelt 
Cc: Paul Walmsley 
Cc: Richard Henderson 
Cc: Richard Weinberger 
Cc: Rich Felker 
Cc: Stefan Kristiansson 
Cc: Sven Schnelle 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Xuerui Wang 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

um: remove unused mm_copy_segments

2022-07-17T21:31:30+00:00

It was already removed by commit c17c02040bf0 ("arch: remove unused
*_segments() macros/functions") but seems to have been accidentally
reintroduced by commit 0500871f21b2 ("Construct init thread stack in the
linker script rather than by union"). Remove it for good.

Signed-off-by: Tobias Klauser 
Signed-off-by: Richard Weinberger

um: stop polluting the namespace with registers.h contents

2021-12-21T20:31:35+00:00

Only one extern in there is needed in processor-generic.h, and it's
not needed anywhere else.  So move it over there and get rid of
the include in processor-generic.h, adding includes of registers.h
to the few files that need the declarations in it.

Signed-off-by: Al Viro 
Signed-off-by: Richard Weinberger

sched: Add wrapper for get_wchan() to keep task blocked

2021-10-15T09:25:14+00:00

Having a stable wchan means the process must be blocked and for it to
stay that way while performing stack unwinding.

Suggested-by: Peter Zijlstra 
Signed-off-by: Kees Cook 
Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Geert Uytterhoeven 
Acked-by: Russell King (Oracle)  [arm]
Tested-by: Mark Rutland  [arm64]
Link: https://lkml.kernel.org/r/20211008111626.332092234@infradead.org