linux-stable.git/arch/parisc, branch linux-4.3.y

parisc: Fix __ARCH_SI_PREAMBLE_SIZE

2016-02-19T22:28:28+00:00

commit e60fc5aa608eb38b47ba4ee058f306f739eb70a0 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 
Signed-off-by: Greg Kroah-Hartman

parisc: Fix syscall restarts

2016-02-19T22:28:28+00:00

commit 71a71fb5374a23be36a91981b5614590b9e722c3 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 
Cc: Mathieu Desnoyers 
Signed-off-by: Greg Kroah-Hartman

parisc: Drop unused MADV_xxxK_PAGES flags from asm/mman.h

2016-02-19T22:28:28+00:00

commit dcbf0d299c00ed4f82ea8d6e359ad88a5182f9b8 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 
Signed-off-by: Greg Kroah-Hartman

parisc: Fixes and cleanups in kernel uapi header files

2016-02-19T22:28:28+00:00

commit d0cf62fb63f760e98244d31396b3b58f3a1e326b upstream.

This patch fixes some bugs and partly cleans up the parisc uapi header
files to what glibc defined:
- compat_semid64_ds was wrong and did not take the endianess into
  account
- ipc64_perm exported userspace types which broke building userspace
  packages on debian (e.g. trinity)
- ipc64_perm needs to use a 32bit mode_t on 64bit kernel
- msqid64_ds and semid64_ds needs unsigned longs for various struct members
- shmid64_ds exported size_t instead of __kernel_size_t

And finally add some compile-time checks for the sizes of those structs
to avoid future breakage.

Runtime-tested with the Linux Test Project (LTP) testsuite.

Reviewed-by: Arnd Bergmann 
Signed-off-by: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

parisc: Use platform_device_register_simple("rtc-generic")

2015-09-08T15:53:48+00:00

Signed-off-by: Helge Deller

parisc: Drop CONFIG_SMP around update_cr16_clocksource()

2015-09-08T15:53:03+00:00

No need to use CONFIG_SMP around update_cr16_clocksource(). It checks for
num_online_cpus() beeing greater than 1, which is always 1 in UP builds.

Signed-off-by: Helge Deller

parisc: Use double word condition in 64bit CAS operation

2015-09-08T14:15:54+00:00

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.

Cc: 
Signed-off-by: John David Anglin 
Signed-off-by: Helge Deller

parisc: Filter out spurious interrupts in PA-RISC irq handler

2015-09-08T13:31:16+00:00

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

Signed-off-by: Helge Deller

parisc: Additionally check for in_atomic() in page fault handler

2015-09-08T13:30:56+00:00

Craig Estey noticed that we didn't checked for in_atomic() in our page fault
handler like other architectures. This commit adds this check by using
faulthandler_disabled() which includes a check for pagefault_disabled() and
in_atomic().

Reported-by: Craig Estey 
Signed-off-by: Helge Deller

parisc: Define ioremap_uc and ioremap_wc

2015-09-08T13:30:37+00:00

Commit 3cc2dac5be3f ("drivers/video/fbdev/atyfb: Replace MTRR UC hole
with strong UC") introduces calls to ioremap_wc and ioremap_uc. This
causes build failures with parisc:allmodconfig. Map the missing
functions to ioremap_nocache.

Fixes: 3cc2dac5be3f ("drivers/video/fbdev/atyfb:
	Replace MTRR UC hole with strong UC")
Cc: Luis R. Rodriguez 
Cc: Paul Gortmaker 
Signed-off-by: Guenter Roeck 
Signed-off-by: Helge Deller