commit 6402e1416255a7bb94834925ba0255c750f54a2d upstream.

Fix various style errors and inconsistencies, no functional changes
intended.
Signed-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-kbuild@vger.kernel.org
Link: https://lkml.kernel.org/r/20191204004633.88660-3-shile.zhang@linux.alibaba.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NCaspar Zhang <caspar@linux.alibaba.com>

commit 3c47b787b6516d2c3cbaa193fe13a83adbaaad1f upstream.

The scripts/sortextable.c code has originally copied some code from
scripts/recordmount.c, which used the same setjmp/longjmp method to
manage control flow.

Meanwhile recordmcount has improved its error handling via:

   3f1df12019f3 ("recordmcount: Rewrite error/success handling").

So rewrite this part of sortextable as well to get rid of the setjmp/longjmp
kludges, with additional refactoring, to make it more readable and
easier to extend.

No functional changes intended.

[ mingo: Rewrote the changelog. ]
Signed-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-kbuild@vger.kernel.org
Link: https://lkml.kernel.org/r/20191204004633.88660-2-shile.zhang@linux.alibaba.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NCaspar Zhang <caspar@linux.alibaba.com>

Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Switch to the generic extable search and sort routines which were introduced
with commit a272858a from Ard Biesheuvel. This saves quite some memory in the
vmlinux binary with the 64bit kernel.
Signed-off-by: NHelge Deller <deller@gmx.de>

Instead of using absolute addresses for both the exception location
and the fixup, use offsets relative to the exception table entry values.
Not only does this cut the size of the exception table in half, it is
also a prerequisite for KASLR, since absolute exception table entries
are subject to dynamic relocation, which is incompatible with the sorting
of the exception table that occurs at build time.

This patch also introduces the _ASM_EXTABLE preprocessor macro (which
exists on x86 as well) and its _asm_extable assembly counterpart, as
shorthands to emit exception table entries.
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add support to scripts/sortextable for handling relocatable (PIE)
executables, whose ELF type is ET_DYN, not ET_EXEC. Other than adding
support for the new type, no changes are needed.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Huge amounts of help from  Andy Lutomirski and Borislav Petkov to
produce this. Andy provided the inspiration to add classes to the
exception table with a clever bit-squeezing trick, Boris pointed
out how much cleaner it would all be if we just had a new field.

Linus Torvalds blessed the expansion with:

  ' I'd rather not be clever in order to save just a tiny amount of space
    in the exception table, which isn't really criticial for anybody. '

The third field is another relative function pointer, this one to a
handler that executes the actions.

We start out with three handlers:

 1: Legacy - just jumps the to fixup IP
 2: Fault - provide the trap number in %ax to the fixup code
 3: Cleaned up legacy for the uaccess error hack
Signed-off-by: NTony Luck <tony.luck@intel.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f6af78fcbd348cf4939875cfda9c19689b5e50b8.1455732970.git.tony.luck@intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Acked-by: NDavid Daney <ddaney.cavm@gmail.com>

Sort the exception table at build-time rather than during boot.

Microblaze is the same case as AARCH64 that's why EM_MICROBLAZE
conditional check was added to allow cross-compilation on machines which
are not running the latest libc-dev.

Inspired by AARCH64 commit adace895 ("arm64: extable: sort the
exception table at build time").
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Avoids wasting cycles at boot specially on slower simulators
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Francois Bedard <fbedard@synopsys.com>
Cc: linux-kernel@vger.kernel.org
Acked-by: NDavid Daney <david.daney@cavium.com>

Building with a large config and -ffunction-sections results in a large
number of sections and sortextable needs to be able to handle that.
Implement support for > 64K sections as modpost does.
Signed-off-by: NJamie Iles <jamie.iles@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NRamkumar Ramachandra <artagnon@gmail.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

As is done for other architectures, sort the exception table at
build-time rather than during boot.

Since sortextable appears to be a standalone C program relying on the
host elf.h to provide EM_AARCH64, I've had to add a conditional check in
order to allow cross-compilation on machines that aren't running a
bleeding-edge libc-dev.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add the ARM machine identifier to sortextable and select the
config option so that we can sort the exception table at compile
time. sortextable relies on a section named __ex_table existing
in the vmlinux, but ARM's linker script places the exception
table in the data section. Give the exception table its own
section so that sortextable can find it.

This allows us to skip the sorting step during boot.

Cc: David Daney <david.daney@cavium.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Tested-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This is the s390 port of 70627654 "x86, extable: Switch to relative
exception table entries".
Reduces the size of our exception tables by 50% on 64 bit builds.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Follow x86 and MIPS and sort the main exception table at build time.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

x86 is now using relative rather than absolute addresses in its
exception table, so we add a sorter for these.  If there are
relocations on the __ex_table section, they are redundant and probably
incorrect after the sort, so they are zeroed out leaving them valid
and consistent.

Also use the unaligned safe accessors from tools/{be,le}_byteshift.h
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Link: http://lkml.kernel.org/r/1335291795-26693-2-git-send-email-ddaney.cavm@gmail.comSigned-off-by: NH. Peter Anvin <hpa@zytor.com>

Using this build-time sort saves time booting as we don't have to burn
cycles sorting the exception table.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Link: http://lkml.kernel.org/r/1334872799-14589-2-git-send-email-ddaney.cavm@gmail.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>