Patch "arch: define weak abort()" has been added to the 4.14-stable tree

Patch "arch: define weak abort()" has been added to the 4.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    arch: define weak abort()

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arch-define-weak-abort.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 7c2c11b208be09c156573fc0076b7b3646e05219 Mon Sep 17 00:00:00 2001
From: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Date: Thu, 14 Dec 2017 15:33:19 -0800
Subject: arch: define weak abort()

From: Sudip Mukherjee <sudipm.mukherjee@gmail.com>

commit 7c2c11b208be09c156573fc0076b7b3646e05219 upstream.

gcc toggle -fisolate-erroneous-paths-dereference (default at -O2
onwards) isolates faulty code paths such as null pointer access, divide
by zero etc.  If gcc port doesnt implement __builtin_trap, an abort() is
generated which causes kernel link error.

In this case, gcc is generating abort due to 'divide by zero' in
lib/mpi/mpih-div.c.

Currently 'frv' and 'arc' are failing.  Previously other arch was also
broken like m32r was fixed by commit d22e3d69ee1a ("m32r: fix build
failure").

Let's define this weak function which is common for all arch and fix the
problem permanently.  We can even remove the arch specific 'abort' after
this is done.

Link: http://lkml.kernel.org/r/1513118956-8718-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Evgeniy Didin <Evgeniy.Didin@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 kernel/exit.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1755,3 +1755,11 @@ Efault:
 	return -EFAULT;
 }
 #endif
+
+__weak void abort(void)
+{
+	BUG();
+
+	/* if that doesn't kill us, halt */
+	panic("Oops failed to kill thread");
+}


Patches currently in stable-queue which might be from sudipm.mukherjee@gmail.com are

queue-4.14/arch-define-weak-abort.patch
queue-4.14/kernel-exit.c-export-abort-to-modules.patch