linux.git/arch/parisc/lib, branch v3.14

parisc: size_t is unsigned, so comparison size < 0 doesn't make sense.

2013-11-19T23:09:42+00:00

Signed-off-by: Helge Deller 
CC: Mikulas Patocka

parisc: do not inline pa_memcpy() internal functions

2013-11-19T22:36:16+00:00

gcc (4.8.x) creates wrong code when the pa_memcpy() functions are
inlined.  Especially in 32bit builds it calculates wrong return values
if we encounter a fault during execution of the memcpy.

Signed-off-by: Helge Deller

parisc: make udelay() SMP-safe

2013-11-07T21:28:26+00:00

Each CPU has it's own Control Register 16 (CR16) which is used as time source
for the udelay() function. But since the CR16 registers across different CPUs
are not synced, we need to recalculate the loop count if we get switched away
to ensure that we really delay as much time as requested.

Signed-off-by: Helge Deller

parisc: provide macro to create exception table entries

2013-11-07T21:25:33+00:00

Provide a macro ASM_EXCEPTIONTABLE_ENTRY() to create exception table
entries and convert all open-coded places to use that macro.

This patch is a first step toward creating a exception table which only
holds 32bit pointers even on a 64bit kernel. That way in my own kernel
I was able to reduce the in-kernel exception table from 44kB to 22kB.

Signed-off-by: Helge Deller

parisc: let probe_kernel_read() capture access to page zero

2013-10-13T15:46:31+00:00

Signed-off-by: Helge Deller

parisc: Fix gcc miscompilation in pa_memcpy()

2013-07-09T20:09:23+00:00

When running the LTP testsuite one may hit this kernel BUG() with the
write06 testcase:

kernel BUG at mm/filemap.c:2023!
CPU: 1 PID: 8614 Comm: writev01 Not tainted 3.10.0-rc7-64bit-c3000+ #6
IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000401e6e84 00000000401e6e88
 IIR: 03ffe01f    ISR: 0000000010340000  IOR: 000001fbe0380820
 CPU:        1   CR30: 00000000bef80000 CR31: ffffffffffffffff
 ORIG_R28: 00000000bdc192c0
 IAOQ[0]: iov_iter_advance+0x3c/0xc0
 IAOQ[1]: iov_iter_advance+0x40/0xc0
 RP(r2): generic_file_buffered_write+0x204/0x3f0
Backtrace:
 [<00000000401e764c>] generic_file_buffered_write+0x204/0x3f0
 [<00000000401eab24>] __generic_file_aio_write+0x244/0x448
 [<00000000401eadc0>] generic_file_aio_write+0x98/0x150
 [<000000004024f460>] do_sync_readv_writev+0xc0/0x130
 [<000000004025037c>] compat_do_readv_writev+0x12c/0x340
 [<00000000402505f8>] compat_writev+0x68/0xa0
 [<0000000040251d88>] compat_SyS_writev+0x98/0xf8

Reason for this crash is a gcc miscompilation in the fault handlers of
pa_memcpy() which return the fault address instead of the copied bytes.
Since this seems to be a generic problem with gcc-4.7.x (and below), it's
better to simplify the fault handlers in pa_memcpy to avoid this problem.

Here is a simple reproducer for the problem:

int main(int argc, char **argv)
{
	int fd, nbytes;
	struct iovec wr_iovec[] = {
		{ "TEST STRING                     ",32},
		{ (char*)0x40005000,32} }; // random memory.
	fd = open(DATA_FILE, O_RDWR | O_CREAT, 0666);
	nbytes = writev(fd, wr_iovec, 2);
	printf("return value = %d, errno %d (%s)\n",
		nbytes, errno, strerror(errno));
	return 0;
}

In addition, John David Anglin wrote:
There is no gcc PR as pa_memcpy is not legitimate C code. There is an
implicit assumption that certain variables will contain correct values
when an exception occurs and the code randomly jumps to one of the
exception blocks.  There is no guarantee of this.  If a PR was filed, it
would likely be marked as invalid.

Signed-off-by: Helge Deller 
Signed-off-by: John David Anglin 
Cc:  # 3.8+
Signed-off-by: Helge Deller

parisc: Provide __ucmpdi2 to resolve undefined references in 32 bit builds.

2013-04-25T20:36:15+00:00

The Debian experimental linux source package (3.8.5-1) build fails
with the following errors:
...
MODPOST 2016 modules
ERROR: "__ucmpdi2" [fs/btrfs/btrfs.ko] undefined!
ERROR: "__ucmpdi2" [drivers/md/dm-verity.ko] undefined!

The attached patch resolves this problem.  It is based on the s390
implementation of ucmpdi2.c.

Signed-off-by: John David Anglin 
Cc: "James E.J. Bottomley" 
Signed-off-by: Helge Deller

parisc: avoid unitialized variable warning in pa_memcpy()

2013-03-02T18:56:27+00:00

Avoid this warning, while still prevent gcc from optimizing away the exception code:
arch/parisc/lib/memcpy.c: In function ‘pa_memcpy’:
arch/parisc/lib/memcpy.c:256:2: warning: ‘dummy’ may be used uninitialized in this function [-Wuninitialized]

Signed-off-by: Helge Deller

[PARISC] update parisc to use generic strncpy_from_user()

2012-05-31T10:14:37+00:00

Signed-off-by: James Bottomley

Disintegrate asm/system.h for PA-RISC

2012-03-28T17:30:02+00:00

Disintegrate asm/system.h for PA-RISC.

Signed-off-by: David Howells 
cc: linux-parisc@vger.kernel.org