linux-stable.git/arch/arc, branch v3.12.39 Linux kernel stable tree arc: mm: Fix build failure 2015-03-12T16:31:26+00:00 Guenter Roeck linux@roeck-us.net 2015-01-30T03:15:33+00:00 077138613c32e2739bda7c0dc35199879d34b51c commit e262eb9381ad51b5de7a9e762ee773bbd25ce650 upstream. Fix misspelled define. Fixes: 33692f27597f ("vm: add VM_FAULT_SIGSEGV handling support") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit e262eb9381ad51b5de7a9e762ee773bbd25ce650 upstream.

Fix misspelled define.

Fixes: 33692f27597f ("vm: add VM_FAULT_SIGSEGV handling support")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
vm: add VM_FAULT_SIGSEGV handling support 2015-03-12T16:31:25+00:00 Linus Torvalds torvalds@linux-foundation.org 2015-01-29T18:51:32+00:00 1868445f57222c177ff2b3ea31f002c1b7eabb08 commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream. The core VM already knows about VM_FAULT_SIGBUS, but cannot return a "you should SIGSEGV" error, because the SIGSEGV case was generally handled by the caller - usually the architecture fault handler. That results in lots of duplication - all the architecture fault handlers end up doing very similar "look up vma, check permissions, do retries etc" - but it generally works. However, there are cases where the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV. In particular, when accessing the stack guard page, libsigsegv expects a SIGSEGV. And it usually got one, because the stack growth is handled by that duplicated architecture fault handler. However, when the generic VM layer started propagating the error return from the stack expansion in commit fee7e49d4514 ("mm: propagate error from stack expansion even for guard page"), that now exposed the existing VM_FAULT_SIGBUS result to user space. And user space really expected SIGSEGV, not SIGBUS. To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those duplicate architecture fault handlers about it. They all already have the code to handle SIGSEGV, so it's about just tying that new return value to the existing code, but it's all a bit annoying. This is the mindless minimal patch to do this. A more extensive patch would be to try to gather up the mostly shared fault handling logic into one generic helper routine, and long-term we really should do that cleanup. Just from this patch, you can generally see that most architectures just copied (directly or indirectly) the old x86 way of doing things, but in the meantime that original x86 model has been improved to hold the VM semaphore for shorter times etc and to handle VM_FAULT_RETRY and other "newer" things, so it would be a good idea to bring all those improvements to the generic case and teach other architectures about them too. Reported-and-tested-by: Takashi Iwai <tiwai@suse.de> Tested-by: Jan Engelhardt <jengelh@inai.de> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots" Cc: linux-arch@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: Fix KSTK_ESP() 2015-03-12T16:31:20+00:00 Vineet Gupta vgupta@synopsys.com 2015-02-27T05:09:17+00:00 47746745842f8dab521acf532b9972aaff146666 commit 13648b0118a24f4fc76c34e6c7b6ccf447e46a2a upstream. /proc/<pid>/maps currently don't annotate stack vma with "[stack]" This is because KSTK_ESP ie expected to return usermode SP of tsk while currently it returns the kernel mode SP of a sleeping tsk. While the fix is trivial, we also need to adjust the ARC kernel stack unwinder to not use KSTK_SP and friends any more. Reported-and-suggested-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 13648b0118a24f4fc76c34e6c7b6ccf447e46a2a upstream.

/proc/<pid>/maps currently don't annotate stack vma with "[stack]"
This is because KSTK_ESP ie expected to return usermode SP of tsk while
currently it returns the kernel mode SP of a sleeping tsk.

While the fix is trivial, we also need to adjust the ARC kernel stack
unwinder to not use KSTK_SP and friends any more.

Reported-and-suggested-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: fix page address calculation if PAGE_OFFSET != LINUX_LINK_BASE 2015-03-01T22:34:21+00:00 Alexey Brodkin abrodkin@synopsys.com 2015-02-12T18:10:11+00:00 02c76a9a9bdb9afb0dc21ada50709729a584b28c commit 06f34e1c28f3608b0ce5b310e41102d3fe7b65a1 upstream. We used to calculate page address differently in 2 cases: 1. In virt_to_page(x) we do --->8--- mem_map + (x - CONFIG_LINUX_LINK_BASE) >> PAGE_SHIFT --->8--- 2. In in pte_page(x) we do --->8--- mem_map + (pte_val(x) - PAGE_OFFSET) >> PAGE_SHIFT --->8--- That leads to problems in case PAGE_OFFSET != CONFIG_LINUX_LINK_BASE - different pages will be selected depending on where and how we calculate page address. In particular in the STAR 9000853582 when gdb attempted to read memory of another process it got improper page in get_user_pages() because this is exactly one of the places where we search for a page by pte_page(). The fix is trivial - we need to calculate page address similarly in both cases. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 06f34e1c28f3608b0ce5b310e41102d3fe7b65a1 upstream.

We used to calculate page address differently in 2 cases:

1. In virt_to_page(x) we do
 --->8---
 mem_map + (x - CONFIG_LINUX_LINK_BASE) >> PAGE_SHIFT
 --->8---

2. In in pte_page(x) we do
 --->8---
 mem_map + (pte_val(x) - PAGE_OFFSET) >> PAGE_SHIFT
 --->8---

That leads to problems in case PAGE_OFFSET != CONFIG_LINUX_LINK_BASE -
different pages will be selected depending on where and how we calculate
page address.

In particular in the STAR 9000853582 when gdb attempted to read memory
of another process it got improper page in get_user_pages() because this
is exactly one of the places where we search for a page by pte_page().

The fix is trivial - we need to calculate page address similarly in both
cases.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: Disable caches in early boot if so configured 2014-11-14T12:14:28+00:00 Vineet Gupta vgupta@synopsys.com 2014-03-07T12:38:11+00:00 d4023bb346873d9f367e174b3e8cc860959296b0 Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
Requested-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: [SMP] General Fixes 2014-11-13T18:02:30+00:00 Vineet Gupta vgupta@synopsys.com 2014-02-24T03:42:50+00:00 1e3b42efefd201e167bef3429ac7c90a9c3d534b commit c3441edd2dea83923421fd6050d2ffdc57696323 upstream. -Pass the expected arg to non-boot park'ing routine (It worked so far because existing SMP backends don't use the arg) -CONFIG_DEBUG_PREEMPT warning Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit c3441edd2dea83923421fd6050d2ffdc57696323 upstream.

-Pass the expected arg to non-boot park'ing routine
 (It worked so far because existing SMP backends don't use the arg)

-CONFIG_DEBUG_PREEMPT warning

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: Implement ptrace(PTRACE_GET_THREAD_AREA) 2014-07-29T15:01:49+00:00 Anton Kolesov Anton.Kolesov@synopsys.com 2014-06-20T16:28:39+00:00 70e52877b68404f462227167ab1c4549e53865fc commit a4b6cb735b25aa84a462a1985e3e43bebaf5beb4 upstream. This patch adds implementation of GET_THREAD_AREA ptrace request type. This is required by GDB to debug NPTL applications. Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit a4b6cb735b25aa84a462a1985e3e43bebaf5beb4 upstream.

This patch adds implementation of GET_THREAD_AREA ptrace request type. This
is required by GDB to debug NPTL applications.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: !PREEMPT: Ensure Return to kernel mode is IRQ safe 2014-05-15T07:55:56+00:00 Vineet Gupta Vineet.Gupta1@synopsys.com 2014-04-30T09:56:45+00:00 ca29d240d7acea0750155dce06778fb1dfd5721d commit 8aa9e85adac609588eeec356e5a85059b3b819ba upstream. There was a very small race window where resume to kernel mode from a Exception Path (or pure kernel mode which is true for most of ARC exceptions anyways), was not disabling interrupts in restore_regs, clobbering the exception regs Anton found the culprit call flow (after many sleepless nights) | 1. we got a Trap from user land | 2. started to service it. | 3. While doing some stuff on user-land memory (I think it is padzero()), | we got a DataTlbMiss | 4. On return from it we are taking "resume_kernel_mode" path | 5. NEED_RESHED is not set, so we go to "return from exception" path in | restore regs. | 6. there seems to be IRQ happening Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Anton Kolesov <Anton.Kolesov@synopsys.com> Cc: Francois Bedard <Francois.Bedard@synopsys.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 8aa9e85adac609588eeec356e5a85059b3b819ba upstream.

There was a very small race window where resume to kernel mode from a
Exception Path (or pure kernel mode which is true for most of ARC
exceptions anyways), was not disabling interrupts in restore_regs,
clobbering the exception regs

Anton found the culprit call flow (after many sleepless nights)

| 1. we got a Trap from user land
| 2. started to service it.
| 3. While doing some stuff on user-land memory (I think it is padzero()),
|     we got a DataTlbMiss
| 4. On return from it we are taking "resume_kernel_mode" path
| 5. NEED_RESHED is not set, so we go to "return from exception" path in
|     restore regs.
| 6. there seems to be IRQ happening

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Anton Kolesov <Anton.Kolesov@synopsys.com>
Cc: Francois Bedard <Francois.Bedard@synopsys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: Remove ARC_HAS_COH_RTSC 2014-05-15T07:55:55+00:00 Richard Weinberger richard@nod.at 2014-02-09T18:48:05+00:00 796f316e0d820502514189f6fda5defee3d640fd commit d345ea2892ae7a2b70f84cf881c20731e43e4993 upstream. The symbol is an orphan, get rid of it. Fixes: 7d0857a54aed ("ARC: [SMP] Disallow RTSC") Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit d345ea2892ae7a2b70f84cf881c20731e43e4993 upstream.

The symbol is an orphan, get rid of it.

Fixes: 7d0857a54aed ("ARC: [SMP] Disallow RTSC")
Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
ARC: [nsimosci] Unbork console 2014-04-18T09:07:21+00:00 Vineet Gupta vgupta@synopsys.com 2014-04-05T10:00:22+00:00 9fc22da2d59cfdfd15655a97d54269d910471c31 commit 61fb4bfc010b0d2940f7fd87acbce6a0f03217cb upstream. Despite the switch to right UART driver (prev patch), serial console still doesn't work due to missing CONFIG_SERIAL_OF_PLATFORM Also fix the default cmdline in DT to not refer to out-of-tree ARC framebuffer driver for console. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Francois Bedard <Francois.Bedard@synopsys.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> 
commit 61fb4bfc010b0d2940f7fd87acbce6a0f03217cb upstream.

Despite the switch to right UART driver (prev patch), serial console
still doesn't work due to missing CONFIG_SERIAL_OF_PLATFORM

Also fix the default cmdline in DT to not refer to out-of-tree
ARC framebuffer driver for console.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Francois Bedard <Francois.Bedard@synopsys.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>