set_page_dirty() will not cope with being handed a page * which is part of
a compound page, but not the master page in that compound page. This case
can occur via access_process_vm() if you attemp to write to another
process's hugepage memory area using ptrace() (causing an oops or hang).
This patch fixes the bug by only calling set_page_dirty() from
access_process_vm() if the page is not a compound page. We already use a
similar fix in bio_set_pages_dirty() for the case of direct io to
hugepages.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The uid_t and gid_t fields appear to present a 32/64-bit userspace/kernel
problem for some archs.
This patch addresses the problem by fixing the size to the largest size for
uid_t/gid_t used in the kernel. This preserves the total size of the event
structure while ensuring that the layouts of the ID change event match in
32 and 64-bit kernels and applications.
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the correct pointer to clear the memory of the return values,
to prevent stack corruption in the callers stackframe.
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This fixes a bug noticed by Paolo Galtieri and fixed for ARCH=ppc in
the previous commit (ppc: fix floating point register corruption).
This fixes the arch/powerpc code by adding preempt_disable/enable,
and also cleans it up a bit by pulling out the code that discards
any lazily-switched CPU register state into a new function, rather
than having that code repeated in three places.
Signed-off-by: Paul Mackerras <paulus@samba.org>
I recently discovered a bug on PPC which causes the floating point
registers to get corrupted when CONFIG_PREEMPT=y.
The problem occurred while running a multi threaded Java application that
does floating point. The problem could be reproduced in anywhere from 2 to
6 hours. With the patch I have included below it ran for over a week
without failure.
Signed-off-by: Paolo Galtieri <pgaltieri@mvista.com>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Tom Rini <trini@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
uverbs needs to track which multicast groups is each qp
attached to, in order to properly detach when cleanup
is performed on device file close.
Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
This patch makes two needlessly global functions static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch contains the following cleanups:
- make needlessly global code static
- ip_conntrack_core.c: ip_conntrack_flush() -> ip_conntrack_flush(void)
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes two needlessly global functions static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
the patch below marks various variables const in net/; the goal is to
move them to the .rodata section so that they can't false-share
cachelines with things that get written to, as well as potentially
helping gcc a bit with optimisations. (these were found using a gcc
patch to warn about such variables)
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
atm_dev_deregister() removes device from atm_dev list immediately to
prevent operations on a phantom device. Decision to free device based
only on ->refcnt now. Remove shutdown_atm_dev() use atm_dev_deregister()
instead. atm_dev_deregister() also asynchronously releases all vccs
related to device.
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use semaphore to protect atm_devs list, as no one need access to it from
interrupt context. Avoid race conditions between atm_dev_register(),
atm_dev_lookup() and atm_dev_deregister(). Fix double spin_unlock() bug.
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Mitchell Blank Jr <mitch@sfgoth.com>
Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Mitchell Blank Jr <mitch@sfgoth.com>
Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Mitchell Blank Jr <mitch@sfgoth.com>
Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
The tcp_ehash hash table gets too big on systems with really big memory.
It is worse on systems with pages larger than 4KB. It wastes memory that
could be better used. It also makes the netstat command slow because reading
/proc/net/tcp and /proc/net/tcp6 needs to go through the full hash table.
The default value should not be larger for larger page sizes. It seems
that the effect of page size is an unintended error dating back a long
time. I also wonder if the default value really should be a larger
fraction of memory for systems with more memory. While systems with
really big ram can afford more space for hash tables, it is not clear to
me that they benefit from increasing the allocation ratio for this table.
The amount of memory allocated is determined by net/ipv4/tcp.c:tcp_init and
mm/page_alloc.c:alloc_large_system_hash.
tcp_init calls alloc_large_system_hash passing parameters-
bucketsize=sizeof(struct tcp_ehash_bucket)
numentries=thash_entries
scale=(num_physpages >= 128 * 1024) ? (25-PAGE_SHIFT) : (27-PAGE_SHIFT)
limit=0
On i386, PAGE_SHIFT is 12 for a page size of 4K
On ia64, PAGE_SHIFT defaults to 14 for a page size of 16K
The num_physpages test above makes the allocation take a larger fraction
of the total memory on systems with larger memory. The threshold size
for a i386 system is 512MB. For an ia64 system with 16KB pages the
threshold is 2GB.
For smaller memory systems-
On i386, scale = (27 - 12) = 15
On ia64, scale = (27 - 14) = 13
For larger memory systems-
On i386, scale = (25 - 12) = 13
On ia64, scale = (25 - 14) = 11
For the rest of this discussion, I'll just track the larger memory case.
The default behavior has numentries=thash_entries=0, so the allocated
size is determined by either scale or by the default limit of 1/16 of
total memory.
In alloc_large_system_hash-
| numentries = (flags & HASH_HIGHMEM) ? nr_all_pages : nr_kernel_pages;
| numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
| numentries >>= 20 - PAGE_SHIFT;
| numentries <<= 20 - PAGE_SHIFT;
At this point, numentries is pages for all of memory, rounded up to the
nearest megabyte boundary.
| /* limit to 1 bucket per 2^scale bytes of low memory */
| if (scale > PAGE_SHIFT)
| numentries >>= (scale - PAGE_SHIFT);
| else
| numentries <<= (PAGE_SHIFT - scale);
On i386, numentries >>= (13 - 12), so numentries is 1/8196 of
bytes of total memory.
On ia64, numentries <<= (14 - 11), so numentries is 1/2048 of
bytes of total memory.
| log2qty = long_log2(numentries);
|
| do {
| size = bucketsize << log2qty;
bucketsize is 16, so size is 16 times numentries, rounded
down to a power of two.
On i386, size is 1/512 of bytes of total memory.
On ia64, size is 1/128 of bytes of total memory.
For smaller systems the results are
On i386, size is 1/2048 of bytes of total memory.
On ia64, size is 1/512 of bytes of total memory.
The large page effect can be removed by just replacing
the use of PAGE_SHIFT with a constant of 12 in the calls to
alloc_large_system_hash. That makes them more like the other uses of
that function from fs/inode.c and fs/dcache.c
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 252ac86553.
It impacts the LSI customers using the mptstm target mode drivers
(source tar-ball at
ftp://ftp.lsil.com/HostAdapterDrivers/linux/Fusion-MPT/mptstm-1.00.13-src.tar.gz
for those who care).
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use copy_user_highpage directly instead of cow_user_page in do_no_page:
in the immediately following page_cache_release, and elsewhere, it is
assuming that new_page is normal. If any VM_PFNMAP driver can get to
do_no_page, it's just a BUG (but not in the case of do_anonymous_page).
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
High Dickins points out that the user virtual address passed to the page
fault handler isn't necessarily page-aligned.
Also, add a comment on why the copy could fail for the user address case.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Increment the PFN field of the PTE so that the tests
on vm_pfn in mm/memory.c match up. The TLB ignores these
lower bits for larger page sizes, so it's OK to set things
like this.
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes locking in megaraid.c, namely:
(1) make sure megaraid_queue release the adapter lock by changing the
code to have a single return
(2) remove the errornous scsi_assign_lock call
Testing by Burton Windle.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Burton Windle <bwindle@fint.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These get created by some drivers that don't generally even want a pfn
remapping at all, but would really mostly prefer to just map pages
they've allocated individually instead.
For now, create a helper function that turns such an incomplete PFN
remapping call into a loop that does that explicit mapping. In the long
run we almost certainly want to export a totally different interface for
that, though.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I image this showed up because of "unused var..." when the changes
occured, because flush_cache_page() is a noop in most places. This
showed up for me on parisc however, where flush_cache_page() is a real
function.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On mem-free HCAs, when posting a long list of send requests, a
doorbell must be rung every 255 requests. Add code to handle this.
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
If ipoib_ib_dev_up() fails after ipoib_ib_dev_open() is called, then
ipoib_ib_dev_stop() needs to be called to clean up.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
This patch contains the following possible cleanups:
- every file should #include the headers containing the prototypes for
it's global functions
- make needlessly global functions static
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
race condition: ipoib_ib_dev_flush is accessing child list without locks.
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Update the pre-CFI Sharp driver sharps.c so it compiles. map_read32 /
map_write32 no longer exist in the kernel so the driver is totally broken
as it stands. The replacement functions use different parameters resulting
in the other changes.
Change collie to use this driver until someone works out why the cfi driver
fails on that machine.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Tested-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The patch below fixes the following sparse warning:
drivers/mtd/maps/nettel.c:482:27: warning: Using plain integer as NULL pointer
Signed-off-by: Luiz Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arjan: drivers/mtd/maps/sc520cdp.c:167: warning: par_table is never written to and should be declared 'const'
arjan: drivers/mtd/maps/pci.c:105: warning: mtd_pci_map is never written to and should be declared 'const'
arjan: mind fixing those up ?
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
ixp4xx updates:
- Handle reads that don't start on a half-word boundary.
- Make it work when CPU is in little-endian mode.
Signed-off-by: John Bowler <jbowler@acm.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Recent models of Intel/Sharp and Spansion CFI flash now have significant
bits in the upper byte of device ID codes, read via what Spansion calls
"autoselect" and Intel calls "read device identifier". Currently these
values are truncated to the low 8 bits in the mtd data structures, as
all CFI read query info has previously been read one byte at a time.
Add a new method for reading 16-bit info, currently just manufacturer
and device codes; datasheets hint at future uses for upper bytes in
other fields.
Signed-off-by: Todd Poynor <tpoynor@mvista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Merge from linux-mips:
Use physical addresses at the interface level, letting drivers remap
them as appropriate.
Signed-off-by: Maciej W. Rozycki <macro@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
ipoib_mcast_alloc() uses kzalloc(), so there's no need to zero out
members of the mcast struct after it's allocated.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Make sure mcast->done is initialized to uncompleted value before we
submit a new query, so that it's safe to wait on.
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
David Gibson
Matt Helsley
Olaf Hering
Paul Mackerras
Paolo Galtieri
Linus Torvalds
Trond Myklebust
Jack Morgenstein
Adrian Bunk
Arjan van de Ven
Chas Williams
Stanislaw Gruszka
Mitchell Blank Jr
Jan Pieter
Dave Jones
Mike Stroyan
Hugh Dickins
David S. Miller
Christoph Hellwig
Ben Collins
Michael S. Tsirkin
Roland Dreier
Richard Purdie
Thomas Gleixner
Luiz Capitulino
Nicolas Pitre
David Woodhouse
John Bowler
Todd Poynor
Maciej W. Rozycki