commit e4dc894b61 upstream.
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Helge Deller <deller@gmx.de>
[bwh: Backported to 3.16 as dependency of commit 35634ffa17
"signal: Always notice exiting tasks"]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 3c229b3f2d upstream.
Fix a long-existing small nasty bug in the map_pages() implementation which
leads to overwriting already written pte entries with zero, *if* map_pages() is
called a second time with an end address which isn't aligned on a pmd boundry.
This happens for example if we want to remap only the text segment read/write
in order to run alternative patching on the code. Exiting the loop when we
reach the end address fixes this.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 615b2665fd upstream.
As found by the ubsan checker, the value of the 'index' variable can be
out of range for the bc[] array:
UBSAN: Undefined behaviour in arch/parisc/kernel/drivers.c:655:21
index 6 is out of range for type 'char [6]'
Backtrace:
[<104fa850>] __ubsan_handle_out_of_bounds+0x68/0x80
[<1019d83c>] check_parent+0xc0/0x170
[<1019d91c>] descend_children+0x30/0x6c
[<1059e164>] device_for_each_child+0x60/0x98
[<1019cd54>] parse_tree_node+0x40/0x54
[<1019d86c>] check_parent+0xf0/0x170
[<1019d91c>] descend_children+0x30/0x6c
[<1059e164>] device_for_each_child+0x60/0x98
[<1019d938>] descend_children+0x4c/0x6c
[<1059e164>] device_for_each_child+0x60/0x98
[<1019cd54>] parse_tree_node+0x40/0x54
[<1019cffc>] hwpath_to_device+0xa4/0xc4
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit d5654e156b upstream.
Make sure that the HPMC (High Priority Machine Check) handler is 16-byte
aligned and that it's length in the IVT is a multiple of 16 bytes.
Otherwise PDC may decide not to call the HPMC crash handler.
Signed-off-by: Helge Deller <deller@gmx.de>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 05f016d2ca upstream.
As noted by Christoph Biedl, passing a pointer size of 4 in the new CAS
implementation causes a kernel crash. The attached patch corrects the
off by one error in the argument validity check.
In reviewing the code, I noticed that we only perform word operations
with the pointer size argument. The subi instruction intentionally uses
a word condition on 64-bit kernels. Nullification was used instead of a
cmpib instruction as the branch should never be taken. The shlw
pseudo-operation generates a depw,z instruction and it clears the target
before doing a shift left word deposit. Thus, we don't need to clip the
upper 32 bits of this argument on 64-bit kernels.
Tested with a gcc testsuite run with a 64-bit kernel. The gcc atomic
code in libgcc is the only direct user of the new CAS implementation
that I am aware of.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 374b3bf8e8 upstream.
As discussed on the debian-hppa list, double-wordcompare and exchange
operations fail on 32-bit kernels. Looking at the code, I realized that
the ",ma" completer does the wrong thing in the "ldw,ma 4(%r26), %r29"
instruction. This increments %r26 and causes the following store to
write to the wrong location.
Note by Helge Deller:
The patch applies cleanly to stable kernel series if this upstream
commit is merged in advance:
f4125cfdb3 ("parisc: Avoid trashing sr2 and sr3 in LWS code").
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Tested-by: Christoph Biedl <debian.axhn@manchmal.in-ulm.de>
Fixes: 8920649120 ("parisc: Implement new LWS CAS supporting 64 bit operations.")
Signed-off-by: Helge Deller <deller@gmx.de>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 247462316f upstream.
When a process runs out of stack the parisc kernel wrongly faults with SIGBUS
instead of the expected SIGSEGV signal.
This example shows how the kernel faults:
do_page_fault() command='a.out' type=15 address=0xfaac2000 in libc-2.24.so[f8308000+16c000]
trap #15: Data TLB miss fault, vm_start = 0xfa2c2000, vm_end = 0xfaac2000
The vma->vm_end value is the first address which does not belong to the vma, so
adjust the check to include vma->vm_end to the range for which to send the
SIGSEGV signal.
This patch unbreaks building the debian libsigsegv package.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit b0f94efd5a upstream.
Architectures with a compat syscall table must put compat_sys_keyctl()
in it, not sys_keyctl(). The parisc architecture was not doing this;
fix it.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 1be7107fbe upstream.
Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.
This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.
Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.
One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications. For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).
Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.
Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.
Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[Hugh Dickins: Backported to 3.16]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 2ad5d52d42 upstream.
In swab.h the "#if BITS_PER_LONG > 32" breaks compiling userspace programs if
BITS_PER_LONG is #defined by userspace with the sizeof() compiler builtin.
Solve this problem by using __BITS_PER_LONG instead. Since we now
#include asm/bitsperlong.h avoid further potential userspace pollution
by moving the #define of SHIFT_PER_LONG to bitops.h which is not
exported to userspace.
This patch unbreaks compiling qemu on hppa/parisc.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit febe42964f upstream.
We have four routines in pacache.S that use temporary alias pages:
copy_user_page_asm(), clear_user_page_asm(), flush_dcache_page_asm() and
flush_icache_page_asm(). copy_user_page_asm() and clear_user_page_asm()
don't purge the TLB entry used for the operation.
flush_dcache_page_asm() and flush_icache_page_asm do purge the entry.
Presumably, this was thought to optimize TLB use. However, the
operation is quite heavy weight on PA 1.X processors as we need to take
the TLB lock and a TLB broadcast is sent to all processors.
This patch removes the purges from flush_dcache_page_asm() and
flush_icache_page_asm.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit c78e710c1c upstream.
The attached change interchanges the order of purging the TLB and
setting the corresponding page table entry. TLB purges are strongly
ordered. It occurred to me one night that setting the PTE first might
have subtle ordering issues on SMP machines and cause random memory
corruption.
A TLB lock guards the insertion of user TLB entries. So after the TLB
is purged, a new entry can't be inserted until the lock is released.
This ensures that the new PTE value is used when the lock is released.
Since making this change, no random segmentation faults have been
observed on the Debian hppa buildd servers.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 5035b230e7 upstream.
This is the second issue I noticed in reviewing the parisc TLB code.
The fic instruction may use either the instruction or data TLB in
flushing the instruction cache. Thus, on machines with a split TLB, we
should also flush the data TLB after setting up the temporary alias
registers.
Although this has no functional impact, I changed the pdtlb and pitlb
instructions to consistently use the index register %r0. These
instructions do not support integer displacements.
Tested on rp3440 and c8000.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit c0452fb9fb upstream.
We are still troubled by occasional random segmentation faults and
memory memory corruption on SMP machines. The causes quite a few
package builds to fail on the Debian buildd machines for parisc. When
gcc-6 failed to build three times in a row, I looked again at the TLB
related code. I found a couple of issues. This is the first.
In general, we need to ensure page table updates and corresponding TLB
purges are atomic. The attached patch fixes an instance in pci-dma.c
where the page table update was not guarded by the TLB lock.
Tested on rp3440 and c8000. So far, no further random segmentation
faults have been observed.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 6ed518328d upstream.
We have one critical section in the syscall entry path in which we switch from
the userspace stack to kernel stack. In the event of an external interrupt, the
interrupt code distinguishes between those two states by analyzing the value of
sr7. If sr7 is zero, it uses the kernel stack. Therefore it's important, that
the value of sr7 is in sync with the currently enabled stack.
This patch now disables interrupts while executing the critical section. This
prevents the interrupt handler to possibly see an inconsistent state which in
the worst case can lead to crashes.
Interestingly, in the syscall exit path interrupts were already disabled in the
critical section which switches back to the userspace stack.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 3eb53b20d7 upstream.
When building gccgo in userspace, errno.h gets parsed and the go include file
sysinfo.go is generated.
Since EREFUSED is defined to the same value as ECONNREFUSED, and ECONNREFUSED
is defined later on in errno.h, this leads to go complaining that EREFUSED
isn't defined yet.
Fix this trivial problem by moving the define of EREFUSED down after
ECONNREFUSED in errno.h (and clean up the indenting while touching this line).
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 8b78f26088 upstream.
One of the debian buildd servers had this crash in the syslog without
any other information:
Unaligned handler failed, ret = -2
clock_adjtime (pid 22578): Unaligned data reference (code 28)
CPU: 1 PID: 22578 Comm: clock_adjtime Tainted: G E 4.5.0-2-parisc64-smp #1 Debian 4.5.4-1
task: 000000007d9960f8 ti: 00000001bde7c000 task.ti: 00000001bde7c000
YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
PSW: 00001000000001001111100000001111 Tainted: G E
r00-03 000000ff0804f80f 00000001bde7c2b0 00000000402d2be8 00000001bde7c2b0
r04-07 00000000409e1fd0 00000000fa6f7fff 00000001bde7c148 00000000fa6f7fff
r08-11 0000000000000000 00000000ffffffff 00000000fac9bb7b 000000000002b4d4
r12-15 000000000015241c 000000000015242c 000000000000002d 00000000fac9bb7b
r16-19 0000000000028800 0000000000000001 0000000000000070 00000001bde7c218
r20-23 0000000000000000 00000001bde7c210 0000000000000002 0000000000000000
r24-27 0000000000000000 0000000000000000 00000001bde7c148 00000000409e1fd0
r28-31 0000000000000001 00000001bde7c320 00000001bde7c350 00000001bde7c218
sr00-03 0000000001200000 0000000001200000 0000000000000000 0000000001200000
sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000
IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000402d2e84 00000000402d2e88
IIR: 0ca0d089 ISR: 0000000001200000 IOR: 00000000fa6f7fff
CPU: 1 CR30: 00000001bde7c000 CR31: ffffffffffffffff
ORIG_R28: 00000002369fe628
IAOQ[0]: compat_get_timex+0x2dc/0x3c0
IAOQ[1]: compat_get_timex+0x2e0/0x3c0
RP(r2): compat_get_timex+0x40/0x3c0
Backtrace:
[<00000000402d4608>] compat_SyS_clock_adjtime+0x40/0xc0
[<0000000040205024>] syscall_exit+0x0/0x14
This means the userspace program clock_adjtime called the clock_adjtime()
syscall and then crashed inside the compat_get_timex() function.
Syscalls should never crash programs, but instead return EFAULT.
The IIR register contains the executed instruction, which disassebles
into "ldw 0(sr3,r5),r9".
This load-word instruction is part of __get_user() which tried to read the word
at %r5/IOR (0xfa6f7fff). This means the unaligned handler jumped in. The
unaligned handler is able to emulate all ldw instructions, but it fails if it
fails to read the source e.g. because of page fault.
The following program reproduces the problem:
#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/mman.h>
int main(void) {
/* allocate 8k */
char *ptr = mmap(NULL, 2*4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
/* free second half (upper 4k) and make it invalid. */
munmap(ptr+4096, 4096);
/* syscall where first int is unaligned and clobbers into invalid memory region */
/* syscall should return EFAULT */
return syscall(__NR_clock_adjtime, 0, ptr+4095);
}
To fix this issue we simply need to check if the faulting instruction address
is in the exception fixup table when the unaligned handler failed. If it
is, call the fixup routine instead of crashing.
While looking at the unaligned handler I found another issue as well: The
target register should not be modified if the handler was unsuccessful.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit f0b22d1bb2 upstream.
Do not load one entry beyond the end of the syscall table when the
syscall number of a traced process equals to __NR_Linux_syscalls.
Similar bug with regular processes was fixed by commit 3bb457af4f
("[PARISC] Fix bug when syscall nr is __NR_Linux_syscalls").
This bug was found by strace test suite.
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 2ef4dfd9d9 upstream.
Handling exceptions from modules never worked on parisc.
It was just masked by the fact that exceptions from modules
don't happen during normal use.
When a module triggers an exception in get_user() we need to load the
main kernel dp value before accessing the exception_data structure, and
afterwards restore the original dp value of the module on exit.
Noticed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit ef72f3110d upstream.
The kernel module testcase (lib/test_user_copy.c) exhibited a kernel
crash on parisc if the parameters for copy_from_user were reversed
("illegal reversed copy_to_user" testcase).
Fix this potential crash by checking the fault handler if the faulting
address is in the exception table.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit e3893027a3 upstream.
We want to avoid the kernel module loader to create function pointers
for the kernel fixup routines of get_user() and put_user(). Changing
the external reference from function type to int type fixes this.
This unbreaks exception handling for get_user() and put_user() when
called from a kernel module.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit e60fc5aa60 upstream.
On a 64bit kernel build the compiler aligns the _sifields union in the
struct siginfo_t on a 64bit address. The __ARCH_SI_PREAMBLE_SIZE define
compensates for this alignment and thus fixes the wait testcase of the
strace package.
The symptoms of a wrong __ARCH_SI_PREAMBLE_SIZE value is that
_sigchld.si_stime variable is missed to be copied and thus after a
copy_siginfo() will have uninitialized values.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 71a71fb537 upstream.
On parisc syscalls which are interrupted by signals sometimes failed to
restart and instead returned -ENOSYS which in the worst case lead to
userspace crashes.
A similiar problem existed on MIPS and was fixed by commit e967ef02
("MIPS: Fix restart of indirect syscalls").
On parisc the current syscall restart code assumes that all syscall
callers load the syscall number in the delay slot of the ble
instruction. That's how it is e.g. done in the unistd.h header file:
ble 0x100(%sr2, %r0)
ldi #syscall_nr, %r20
Because of that assumption the current code never restored %r20 before
returning to userspace.
This assumption is at least not true for code which uses the glibc
syscall() function, which instead uses this syntax:
ble 0x100(%sr2, %r0)
copy regX, %r20
where regX depend on how the compiler optimizes the code and register
usage.
This patch fixes this problem by adding code to analyze how the syscall
number is loaded in the delay branch and - if needed - copy the syscall
number to regX prior returning to userspace for the syscall restart.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit dcbf0d299c upstream.
Drop the MADV_xxK_PAGES flags, which were never used and were from a proposed
API which was never integrated into the generic Linux kernel code.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit b1b4e435e4 upstream.
When detecting a serial port on newer PA-RISC machines (with iosapic) we have a
long way to go to find the right IRQ line, registering it, then registering the
serial port and the irq handler for the serial port. During this phase spurious
interrupts for the serial port may happen which then crashes the kernel because
the action handler might not have been set up yet.
So, basically it's a race condition between the serial port hardware and the
CPU which sets up the necessary fields in the irq sructs. The main reason for
this race is, that we unmask the serial port irqs too early without having set
up everything properly before (which isn't easily possible because we need the
IRQ number to register the serial ports).
This patch is a work-around for this problem. It adds checks to the CPU irq
handler to verify if the IRQ action field has been initialized already. If not,
we just skip this interrupt (which isn't critical for a serial port at bootup).
The real fix would probably involve rewriting all PA-RISC specific IRQ code
(for CPU, IOSAPIC, GSC and EISA) to use IRQ domains with proper parenting of
the irq chips and proper irq enabling along this line.
This bug has been in the PA-RISC port since the beginning, but the crashes
happened very rarely with currently used hardware. But on the latest machine
which I bought (a C8000 workstation), which uses the fastest CPUs (4 x PA8900,
1GHz) and which has the largest possible L1 cache size (64MB each), the kernel
crashed at every boot because of this race. So, without this patch the machine
would currently be unuseable.
For the record, here is the flow logic:
1. serial_init_chip() in 8250_gsc.c calls iosapic_serial_irq().
2. iosapic_serial_irq() calls txn_alloc_irq() to find the irq.
3. iosapic_serial_irq() calls cpu_claim_irq() to register the CPU irq
4. cpu_claim_irq() unmasks the CPU irq (which it shouldn't!)
5. serial_init_chip() then registers the 8250 port.
Problems:
- In step 4 the CPU irq shouldn't have been registered yet, but after step 5
- If serial irq happens between 4 and 5 have finished, the kernel will crash
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
[ luis: backported to 3.16: used Helge's backport ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 1b59ddfcf1 upstream.
The attached change fixes the condition used in the "sub" instruction.
A double word comparison is needed. This fixes the 64-bit LWS CAS
operation on 64-bit kernels.
I can now enable 64-bit atomic support in GCC.
Signed-off-by: John David Anglin <dave.anglin>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit d045c77c1a upstream.
On architectures where the stack grows upwards (CONFIG_STACK_GROWSUP=y,
currently parisc and metag only) stack randomization sometimes leads to crashes
when the stack ulimit is set to lower values than STACK_RND_MASK (which is 8 MB
by default if not defined in arch-specific headers).
The problem is, that when the stack vm_area_struct is set up in fs/exec.c, the
additional space needed for the stack randomization (as defined by the value of
STACK_RND_MASK) was not taken into account yet and as such, when the stack
randomization code added a random offset to the stack start, the stack
effectively got smaller than what the user defined via rlimit_max(RLIMIT_STACK)
which then sometimes leads to out-of-stack situations and crashes.
This patch fixes it by adding the maximum possible amount of memory (based on
STACK_RND_MASK) which theoretically could be added by the stack randomization
code to the initial stack size. That way, the user-defined stack size is always
guaranteed to be at minimum what is defined via rlimit_max(RLIMIT_STACK).
This bug is currently not visible on the metag architecture, because on metag
STACK_RND_MASK is defined to 0 which effectively disables stack randomization.
The changes to fs/exec.c are inside an "#ifdef CONFIG_STACK_GROWSUP"
section, so it does not affect other platformws beside those where the
stack grows upwards (parisc and metag).
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 33692f2759 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 fee7e49d45 ("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
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ luis: backported to 3.16:
- file renamed: arch/powerpc/mm/copro_fault.c ->
arch/powerpc/platforms/cell/spu_fault.c
- dropped changes to arch/nios2/mm/fault.c ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 45db07382a upstream.
The __ldcw macro has a problem when its argument needs to be reloaded from
memory. The output memory operand and the input register operand both need to
be reloaded using a register in class R1_REGS when generating 64-bit code.
This fails because there's only a single register in the class. Instead, use a
memory clobber. This also makes the __ldcw macro a compiler memory barrier.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 2fe749f50b upstream.
Switch over the msgctl, shmat, shmctl and semtimedop syscalls to use the compat
layer. The problem was found with the debian procenv package, which called
shmctl(0, SHM_INFO, &info);
in which the shmctl syscall then overwrote parts of the surrounding areas on
the stack on which the info variable was stored and thus lead to a segfault
later on.
Additionally fix the definition of struct shminfo64 to use unsigned longs like
the other architectures. This has no impact on userspace since we only have a
32bit userspace up to now.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit d26a7730b5 upstream.
In spite of what the GCC manual says, the -mfast-indirect-calls has
never been supported in the 64-bit parisc compiler. Indirect calls have
always been done using function descriptors irrespective of the
-mfast-indirect-calls option.
Recently, it was noticed that a function descriptor was always requested
when the -mfast-indirect-calls option was specified. This caused
problems when the option was used in application code and doesn't make
any sense because the whole point of the option is to avoid using a
function descriptor for indirect calls.
Fixing this broke 64-bit kernel builds.
I will fix GCC but for now we need the attached change. This results in
the same kernel code as before.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8920649120 upstream.
The current LWS cas only works correctly for 32bit. The new LWS allows
for CAS operations of variable size.
Signed-off-by: Guy Martin <gmsoft@tuxicoman.be>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
alloc_bootmem and related function always return zeroed region of
memory. Thus a memset after calls to these functions is unnecessary.
The following Coccinelle semantic patch was used for making the change:
@@
expression E,E1;
@@
E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
- memset(E,0,E1);
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Helge Deller <deller@gmx.de>
The sa_restorer field in struct sigaction is obsolete and no longer in
the parisc implementation. However, the core code assumes the field is
present if SA_RESTORER is defined. So, the define needs to be removed.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Pull parisc fixes from Helge Deller:
"The major patch in here is one which fixes the fanotify_mark() syscall
in the compat layer of the 64bit parisc kernel. It went unnoticed so
long, because the calling syntax when using a 64bit parameter in a
32bit syscall is quite complex and even worse, it may be even
different if you call syscall() or the glibc wrapper. This patch
makes the kernel accept the calling convention when called by the
glibc wrapper.
The other two patches are trivial and remove unused headers, #includes
and adds the serial ports of the fastest C8000 workstation to the
parisc-kernel internal hardware database"
* 'parisc-3.16-5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: drop unused defines and header includes
parisc: fix fanotify_mark() syscall on 32bit compat kernel
parisc: add serial ports of C8000/1GHz machine to hardware database
On parisc we can not use the existing compat implementation for fanotify_mark()
because for the 64bit mask parameter the higher and lower 32bits are ordered
differently than what the compat function expects from big endian
architectures.
Specifically:
It finally turned out, that on hppa we end up with different assignments
of parameters to kernel arguments depending on if we call the glibc
wrapper function
int fanotify_mark (int __fanotify_fd, unsigned int __flags,
uint64_t __mask, int __dfd, const char *__pathname);
or directly calling the syscall manually
syscall(__NR_fanotify_mark, ...)
Reason is, that the syscall() function is implemented as C-function and
because we now have the sysno as first parameter in front of the other
parameters the compiler will unexpectedly add an empty paramenter in
front of the u64 value to ensure the correct calling alignment for 64bit
values.
This means, on hppa you can't simply use syscall() to call the kernel
fanotify_mark() function directly, but you have to use the glibc
function instead.
This patch fixes the kernel in the hppa-arch specifc coding to adjust
the parameters in a way as if userspace calls the glibc wrapper function
fanotify_mark().
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 3.13+
Strings library contributed to glibc but re-licensed under GPLv2)
- Optimised crypto algorithms making use of the ARMv8 crypto extensions
(together with kernel API for using FPSIMD instructions in interrupt
context)
- Ftrace support
- CPU topology parsing from DT
- ESR_EL1 (Exception Syndrome Register) exposed to user space signal
handlers for SIGSEGV/SIGBUS (useful to emulation tools like Qemu)
- 1GB section linear mapping if applicable
- Barriers usage clean-up
- Default pgprot clean-up
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux into next
Pull arm64 updates from Catalin Marinas:
- Optimised assembly string/memory routines (based on the AArch64
Cortex Strings library contributed to glibc but re-licensed under
GPLv2)
- Optimised crypto algorithms making use of the ARMv8 crypto extensions
(together with kernel API for using FPSIMD instructions in interrupt
context)
- Ftrace support
- CPU topology parsing from DT
- ESR_EL1 (Exception Syndrome Register) exposed to user space signal
handlers for SIGSEGV/SIGBUS (useful to emulation tools like Qemu)
- 1GB section linear mapping if applicable
- Barriers usage clean-up
- Default pgprot clean-up
Conflicts as per Catalin.
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (57 commits)
arm64: kernel: initialize broadcast hrtimer based clock event device
arm64: ftrace: Add system call tracepoint
arm64: ftrace: Add CALLER_ADDRx macros
arm64: ftrace: Add dynamic ftrace support
arm64: Add ftrace support
ftrace: Add arm64 support to recordmcount
arm64: Add 'notrace' attribute to unwind_frame() for ftrace
arm64: add __ASSEMBLY__ in asm/insn.h
arm64: Fix linker script entry point
arm64: lib: Implement optimized string length routines
arm64: lib: Implement optimized string compare routines
arm64: lib: Implement optimized memcmp routine
arm64: lib: Implement optimized memset routine
arm64: lib: Implement optimized memmove routine
arm64: lib: Implement optimized memcpy routine
arm64: defconfig: enable a few more common/useful options in defconfig
ftrace: Make CALLER_ADDRx macros more generic
arm64: Fix deadlock scenario with smp_send_stop()
arm64: Fix machine_shutdown() definition
arm64: Support arch_irq_work_raise() via self IPIs
...
Here is the big USB driver pull request for 3.16-rc1.
Nothing huge here, but lots of little things in the USB core, and in
lots of drivers. Hopefully the USB power management will be work better
now that it has been reworked to do per-port power control dynamically.
There's also a raft of gadget driver updates and fixes, CONFIG_USB_DEBUG
is finally gone now that everything has been converted over to the
dynamic debug inteface, the last hold-out drivers were cleaned up and
the config option removed. There were also other minor things all
through the drivers/usb/ tree, the shortlog shows this pretty well.
All have been in linux-next, including the very last patch, which came
from linux-next to fix a build issue on some platforms.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb into next
Pull USB driver updates from Greg KH:
"Here is the big USB driver pull request for 3.16-rc1.
Nothing huge here, but lots of little things in the USB core, and in
lots of drivers. Hopefully the USB power management will be work
better now that it has been reworked to do per-port power control
dynamically. There's also a raft of gadget driver updates and fixes,
CONFIG_USB_DEBUG is finally gone now that everything has been
converted over to the dynamic debug inteface, the last hold-out
drivers were cleaned up and the config option removed. There were
also other minor things all through the drivers/usb/ tree, the
shortlog shows this pretty well.
All have been in linux-next, including the very last patch, which came
from linux-next to fix a build issue on some platforms"
* tag 'usb-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (314 commits)
usb: hub_handle_remote_wakeup() only exists for CONFIG_PM=y
USB: orinoco_usb: remove CONFIG_USB_DEBUG support
USB: media: lirc: igorplugusb: remove CONFIG_USB_DEBUG support
USB: media: streamzap: remove CONFIG_USB_DEBUG
USB: media: redrat3: remove CONFIG_USB_DEBUG usage
USB: media: redrat3: remove unneeded tracing macro
usb: qcserial: add additional Sierra Wireless QMI devices
usb: host: max3421-hcd: Use module_spi_driver
usb: host: max3421-hcd: Allow platform-data to specify Vbus polarity
usb: host: max3421-hcd: fix "spi_rd8" uses dynamic stack allocation warning
usb: host: max3421-hcd: Fix missing unlock in max3421_urb_enqueue()
usb: qcserial: add Netgear AirCard 341U
Documentation: dt-bindings: update xhci-platform DT binding for R-Car H2 and M2
usb: host: xhci-plat: add xhci_plat_start()
usb: host: max3421-hcd: Fix potential NULL urb dereference
Revert "usb: gadget: net2280: Add support for PLX USB338X"
USB: usbip: remove CONFIG_USB_DEBUG reference
USB: remove CONFIG_USB_DEBUG from defconfig files
usb: resume child device when port is powered on
usb: hub_handle_remote_wakeup() depends on CONFIG_PM_RUNTIME=y
...
Now that CONFIG_USB_DEBUG is gone, remove it from a number of defconfig
files that were enabling it.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pcibios_penalize_isa_irq() is only implemented by x86 now, and legacy ISA
is not used by some architectures. Make pcibios_penalize_isa_irq() a
__weak function to simplify the code. This removes the need for new
platforms to add stub implementations of pcibios_penalize_isa_irq().
[bhelgaas: changelog, comments]
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>