linux-stable.git/arch/sparc/lib, branch linux-4.9.y

sparc64: fix pci_iounmap() when CONFIG_PCI is not set

2021-10-09T11:25:59+00:00

[ Upstream commit d8b1e10a2b8efaf71d151aa756052fbf2f3b6d57 ]

Guenter reported [1] that the pci_iounmap() changes remain problematic,
with sparc64 allnoconfig and tinyconfig still not building due to the
header file changes and confusion with the arch-specific pci_iounmap()
implementation.

I'm pretty convinced that sparc should just use GENERIC_IOMAP instead of
doing its own thing, since it turns out that the sparc64 version of
pci_iounmap() is somewhat buggy (see [2]).  But in the meantime, this
just fixes the build by avoiding the trivial re-definition of the empty
case.

Link: https://lore.kernel.org/lkml/20210920134424.GA346531@roeck-us.net/ [1]
Link: https://lore.kernel.org/lkml/CAHk-=wgheheFx9myQyy5osh79BAazvmvYURAtub2gQtMvLrhqQ@mail.gmail.com/ [2]
Reported-by: Guenter Roeck 
Cc: David Miller 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

sparc32: fix a user-triggerable oops in clear_user()

2021-03-03T16:44:44+00:00

commit 7780918b36489f0b2f9a3749d7be00c2ceaec513 upstream.

Back in 2.1.29 the clear_user() guts (__bzero()) had been merged
with memset().  Unfortunately, while all exception handlers had been
copied, one of the exception table entries got lost.  As the result,
clear_user() starting at 128*n bytes before the end of page and
spanning between 8 and 127 bytes into the next page would oops when
the second page is unmapped.  It's trivial to reproduce - all
it takes is

main()
{
	int fd = open("/dev/zero", O_RDONLY);
	char *p = mmap(NULL, 16384, PROT_READ|PROT_WRITE,
			MAP_PRIVATE|MAP_ANON, -1, 0);
	munmap(p + 8192, 8192);
	read(fd, p + 8192 - 128, 192);
}

which had been oopsing since March 1997.  Says something about
the quality of test coverage... ;-/  And while today sparc32 port
is nearly dead, back in '97 it had been very much alive; in fact,
sparc64 had only been in mainline for 3 months by that point...

Cc: stable@kernel.org
Fixes: v2.1.29
Signed-off-by: Al Viro 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sparc64: Don't clibber fixed registers in __multi4.

2018-06-06T14:44:39+00:00

commit 79db795833bf5c3e798bcd7a5aeeee3fb0505927 upstream.

%g4 and %g5 are fixed registers used by the kernel for the thread
pointer and the per-cpu offset.  Use %o4 and %g7 instead.

Diagnosis by Anthony Yznaga.

Fixes: 1b4af13ff2cc ("sparc64: Add __multi3 for gcc 7.x and later.")
Reported-by: Anatoly Pugachev 
Tested-by: Anatoly Pugachev 
Signed-off-by: David S. Miller 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

sparc64: Fix exception handling in UltraSPARC-III memcpy.

2017-08-11T15:49:34+00:00

[ Upstream commit 0ede1c401332173ab0693121dc6cde04a4dbf131 ]

Mikael Pettersson reported that some test programs in the strace-4.18
testsuite cause an OOPS.

After some debugging it turns out that garbage values are returned
when an exception occurs, causing the fixup memset() to be run with
bogus arguments.

The problem is that two of the exception handler stubs write the
successfully copied length into the wrong register.

Fixes: ee841d0aff64 ("sparc64: Convert U3copy_{from,to}_user to accurate exception reporting.")
Reported-by: Mikael Pettersson 
Tested-by: Mikael Pettersson 
Reviewed-by: Sam Ravnborg 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sparc64: Add __multi3 for gcc 7.x and later.

2017-06-14T13:05:53+00:00

[ Upstream commit 1b4af13ff2cc6897557bb0b8d9e2fad4fa4d67aa ]

Reported-by: Waldemar Brodkorb 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sparc64: fix fault handling in NGbzero.S and GENbzero.S

2017-05-14T12:00:20+00:00

commit 3c7f62212018b904ae17f5636ead18a4dca3a88f upstream.

When any of the functions contained in NGbzero.S and GENbzero.S
vector through *bzero_from_clear_user, we may end up taking a
fault when executing one of the store alternate address space
instructions. If this happens, the exception handler does not
restore the %asi register.

This commit fixes the issue by introducing a new exception
handler that ensures the %asi register is restored when
a fault is handled.

Orabug: 25577560

Signed-off-by: Dave Aldridge 
Reviewed-by: Rob Gardner 
Reviewed-by: Babu Moger 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sparc64: Delete now unused user copy fixup functions.

2016-10-25T04:26:04+00:00

Now that all of the user copy routines are converted to return
accurate residual lengths when an exception occurs, we no longer need
the broken fixup routines.

Signed-off-by: David S. Miller

sparc64: Convert U3copy_{from,to}_user to accurate exception reporting.

2016-10-25T04:20:35+00:00

Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.

Signed-off-by: David S. Miller

sparc64: Convert NG2copy_{from,to}_user to accurate exception reporting.

2016-10-25T03:46:44+00:00

Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.

Signed-off-by: David S. Miller

sparc64: Convert NGcopy_{from,to}_user to accurate exception reporting.

2016-10-25T02:32:12+00:00

Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.

Signed-off-by: David S. Miller