commit 3b35a171060f846b08b48646b38c30b5d57d17ff upstream.

do_page_fault() and do_entUna() are special because they use
non-standard stack frame layout. Fix them manually.

Cc: stable@vger.kernel.org
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Ivan Kokshaysky <ink@unseen.parts>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.

auto-generated by the following:

for i in `git grep -l -w asm/unaligned.h`; do
	sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
	sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

All EV4 machines are already gone, and the remaining EV5 based machines
all support the slightly more modern EV56 generation as well.
Debian only supports EV56 and later.

Drop both of these and build kernels optimized for EV56 and higher
when the "generic" options is selected, tuning for an out-of-order
EV6 pipeline, same as Debian userspace.

Since this was the only supported architecture without 8-bit and
16-bit stores, common kernel code no longer has to worry about
aligning struct members, and existing workarounds from the block
and tty layers can be removed.

The alpha memory management code no longer needs an abstraction
for the differences between EV4 and EV5+.

Link: https://lists.debian.org/debian-alpha/2023/05/msg00009.html
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

some architectures run into a -Wmissing-prototypes warning
for trap_init()

arch/microblaze/kernel/traps.c:21:6: warning: no previous prototype for 'trap_init' [-Wmissing-prototypes]

Include the right header to avoid this consistently, removing
the extra declarations on m68k and x86 that were added as local
workarounds already.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Type 3 instruction fault (FPU insn with FPU disabled) is handled
by quietly enabling FPU and returning.  Which is fine, except that
we need to do that both for fault in userland and in the kernel;
the latter *can* legitimately happen - all it takes is this:

.global _start
_start:
        call_pal 0xae
	lda $0, 0
	ldq $0, 0($0)

- call_pal CLRFEN to clear "FPU enabled" flag and arrange for
a signal delivery (SIGSEGV in this case).

Fixed by moving the handling of type 3 into the common part of
do_entIF(), before we check for kernel vs. user mode.

Incidentally, the check for kernel mode is unidiomatic; the normal
way to do that is !user_mode(regs).  The difference is that
the open-coded variant treats any of bits 63..3 of regs->ps being
set as "it's user mode" while the normal approach is to check just
the bit 3.  PS is a 4-bit register and regs->ps always will have
bits 63..4 clear, so the open-coded variant here is actually equivalent
to !user_mode(regs).  Harder to follow, though...

Cc: stable@vger.kernel.org
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Use is_kernel_text() helper to simplify code.

Link: https://lkml.kernel.org/r/20210930071143.63410-12-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull siginfo si_trapno updates from Eric Biederman:
 "The full set of si_trapno changes was not appropriate as a fix for the
  newly added SIGTRAP TRAP_PERF, and so I postponed the rest of the
  related cleanups.

  This is the rest of the cleanups for si_trapno that reduces it from
  being a really weird arch special case that is expect to be always
  present (but isn't) on the architectures that support it to being yet
  another field in the _sigfault union of struct siginfo.

  The changes have been reviewed and marinated in linux-next. With the
  removal of this awkward special case new code (like SIGTRAP TRAP_PERF)
  that works across architectures should be easier to write and
  maintain"

* 'siginfo-si_trapno-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  signal: Rename SIL_PERF_EVENT SIL_FAULT_PERF_EVENT for consistency
  signal: Verify the alignment and size of siginfo_t
  signal: Remove the generic __ARCH_SI_TRAPNO support
  signal/alpha: si_trapno is only used with SIGFPE and SIGTRAP TRAP_UNK
  signal/sparc: si_trapno is only used with SIGILL ILL_ILLTRP
  arm64: Add compile-time asserts for siginfo_t offsets
  arm: Add compile-time asserts for siginfo_t offsets
  sparc64: Add compile-time asserts for siginfo_t offsets

Fix some spelling mistakes in comments:
delarations ==> declarations
softare ==> software
suffiently ==> sufficiently
requred ==> required
unaliged ==> unaligned

Signed-off-by: gushengxian <gushengxian@yulong.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

While reviewing the signal handlers on alpha it became clear that
si_trapno is only set to a non-zero value when sending SIGFPE and when
sending SITGRAP with si_code TRAP_UNK.

Add send_sig_fault_trapno and send SIGTRAP TRAP_UNK, and SIGFPE with it.

Remove the define of __ARCH_SI_TRAPNO and remove the always zero
si_trapno parameter from send_sig_fault and force_sig_fault.

v1: https://lkml.kernel.org/r/m1eeers7q7.fsf_-_@fess.ebiederm.org
v2: https://lkml.kernel.org/r/20210505141101.11519-7-ebiederm@xmission.com
Link: https://lkml.kernel.org/r/87h7gvxx7l.fsf_-_@disp2133
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>