linux/arch
Maciej W. Rozycki 5a1aca4469 MIPS: Fix FCSR Cause bit handling for correct SIGFPE issue
Sanitize FCSR Cause bit handling, following a trail of past attempts:

* commit 4249548454 ("MIPS: ptrace: Fix FP context restoration FCSR
regression"),

* commit 443c44032a ("MIPS: Always clear FCSR cause bits after
emulation"),

* commit 64bedffe49 ("MIPS: Clear [MSA]FPE CSR.Cause after
notify_die()"),

* commit b1442d39fa ("MIPS: Prevent user from setting FCSR cause
bits"),

* commit b54d2901517d ("Properly handle branch delay slots in connection
with signals.").

Specifically do not mask these bits out in ptrace(2) processing and send
a SIGFPE signal instead whenever a matching pair of an FCSR Cause and
Enable bit is seen as execution of an affected context is about to
resume.  Only then clear Cause bits, and even then do not clear any bits
that are set but masked with the respective Enable bits.  Adjust Cause
bit clearing throughout code likewise, except within the FPU emulator
proper where they are set according to IEEE 754 exceptions raised as the
operation emulated executed.  Do so so that any IEEE 754 exceptions
subject to their default handling are recorded like with operations
executed by FPU hardware.

Signed-off-by: Maciej W. Rozycki <macro@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14460/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-11-04 01:28:41 +01:00
..
alpha Merge branch 'gup_flag-cleanups' 2016-10-19 08:39:47 -07:00
arc ARC: module: print pretty section names 2016-10-28 10:10:29 -07:00
arm ARM: SoC fixes 2016-10-29 12:07:29 -07:00
arm64 ARM: SoC fixes 2016-10-29 12:07:29 -07:00
avr32 Merge branch 'akpm' (patches from Andrew) 2016-10-07 21:38:00 -07:00
blackfin Merge branch 'gup_flag-cleanups' 2016-10-19 08:39:47 -07:00
c6x nmi_backtrace: generate one-line reports for idle cpus 2016-10-07 18:46:30 -07:00
cris cris/arch-v32: cryptocop: print a hex number after a 0x prefix 2016-10-27 18:43:43 -07:00
frv Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-11 23:38:39 -07:00
h8300 h8300: fix syscall restarting 2016-10-27 18:43:42 -07:00
hexagon nmi_backtrace: generate one-line reports for idle cpus 2016-10-07 18:46:30 -07:00
ia64 Merge branch 'gup_flag-cleanups' 2016-10-19 08:39:47 -07:00
m32r mm: replace access_process_vm() write parameter with gup_flags 2016-10-19 08:31:25 -07:00
m68k Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-10-14 14:26:58 -07:00
metag Metag architecture fixes for v4.9-rc1 2016-10-14 11:11:39 -07:00
microblaze Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-11 23:38:39 -07:00
mips MIPS: Fix FCSR Cause bit handling for correct SIGFPE issue 2016-11-04 01:28:41 +01:00
mn10300 Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-11 23:38:39 -07:00
nios2 nios2 update for v4.9-rc1 2016-10-10 11:31:19 -07:00
openrisc Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-11 23:38:39 -07:00
parisc Merge branch 'parisc-4.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2016-10-11 23:59:07 -07:00
powerpc powerpc fixes for 4.9 #4 2016-10-28 16:52:28 -07:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2016-10-27 14:16:30 -07:00
score Merge branch 'gup_flag-cleanups' 2016-10-19 08:39:47 -07:00
sh Minor changes to improve J2 support and match Kconfig expectations of 2016-10-19 11:21:06 -07:00
sparc Merge branch 'gup_flag-cleanups' 2016-10-19 08:39:47 -07:00
tile tile: use simpler API for random address requests 2016-10-11 15:06:32 -07:00
um nmi_backtrace: generate one-line reports for idle cpus 2016-10-07 18:46:30 -07:00
unicore32 unicore32: use simpler API for random address requests 2016-10-11 15:06:32 -07:00
x86 x86/smpboot: Init apic mapping before usage 2016-10-29 14:00:46 +02:00
xtensa Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-11 23:38:39 -07:00
.gitignore
Kconfig This adds a new gcc plugin named "latent_entropy". It is designed to 2016-10-15 10:03:15 -07:00