This change moves around port assignment so that it happens before any
memory is allocated. This allows memory to be allocated on an appropriate
CPU, which improves performance for users of /dev/ipath.
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
IB/ipath: Fix EEPROM read when driver is compiled with -Os
The EEPROM is read via programmable I/O pins. When the driver
is compiled -Os, the CPU can speculatively read the I/O
value before it is valid. This patch fixes the problem.
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
IB/ipath: Fix and recover TXE piobuf and PBC parity errors
We can sometimes trigger parity errors due to processor speculative
reads to our write-combined memory (mostly seen on Woodcrest). Add a
stats counter for these.
Factored out the sendbuffererror buffer cancellation code so it can be
used in the new handling; suppress likely subsequent error messages if
within two jiffies of the cancellation.
Also restore 2 dropped TXE lines on hwe_bitsextant noticed while
debugging.
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
IB/ipath: Fix mismatch in shifts and masks for printing debug info
Fixed mismatch in linkstate/trainingstate shifts and masks in the
IPATH_IBSTATE_MASK macro. It kept some linktrainingstates
from being printed correctly in debug; no functionality issue unless
I misread the code.
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
IB/ipath: Driver support for userspace sharing of HW contexts
This allows multiple userspace processes to share a single hardware
context in a master/slave arrangement. It is backwards binary compatible
with existing userspace.
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
IB/iser: DMA unmap unaligned for RDMA data before touching it
iSER uses the DMA mapping api to map the page holding the
SCSI command data to the HCA DMA address space. When the
command data is not aligned for RDMA, the data is copied
to/from an allocated buffer which in turn is used for
executing this command. The pages associated with the
command must be unmapped before being touched.
Signed-off-by: Erez Zilber <erezz@voltaire.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
IB/iser: Have iSER data transaction object point to iSER conn
iSER uses a data transaction object (struct iser_dto) as part
of its IB data descriptors (struct iser_desc) management.
It also uses a hierarchy of connection structures pointing to
each other. A DTO may exist even after the iscsi_iser connection
pointed by it is destroyed (eg one that is bound to a post
receive buffer which was flushed by the IB HW). Hence DTOs need
point to the lowest connection, which is struct iser_conn.
Signed-off-by: Erez Zilber <erezz@voltaire.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
Eric Sesterhenn [Thu, 28 Sep 2006 17:38:32 +0000 (10:38 -0700)]
RDMA/amso1100: Fix error path in c2_llp_accept()
Another NULL dereference spotted by the Coverity checker (cid #1395):
In case we can't alloc the vq_req, we goto bail1, where we call
vq_req_free(c2dev, vq_req); which then dereferences vq_req.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Acked-by: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
[IA64] minor reformatting to vmlinux.lds.S
[IA64] CMC/CPE: Reverse the order of fetching log and checking poll threshold
[IA64] PAL calls need physical mode, stacked
[IA64] ar.fpsr not set on MCA/INIT kernel entry
[IA64] printing support for MCA/INIT
[IA64] trim output of show_mem()
[IA64] show_mem() printk levels
[IA64] Make gp value point to Region 5 in mca handler
Revert "[IA64] Unwire set/get_robust_list"
[IA64] Implement futex primitives
[IA64-SGI] Do not request DMA memory for BTE
[IA64] Move perfmon tables from thread_struct to pfm_context
[IA64] Add interface so modules can discover whether multithreading is on.
[IA64] kprobes: fixup the pagefault exception caused by probehandlers
[IA64] kprobe opcode 16 bytes alignment on IA64
[IA64] esi-support
[IA64] Add "model name" to /proc/cpuinfo
Andrew Morton [Wed, 27 Sep 2006 08:51:15 +0000 (01:51 -0700)]
[PATCH] x86: use probe_kernel_address in handle_BUG()
Avoid possible deadlock on a BUG() inside down_write(mmap_sem). The deadlock
can only occur if something has gone horridly wrong, because a fault here
shouldn't happen.
Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Ingo Oeser pointed out that because current expands to an inline function
it is more space efficient and somewhat faster to simply keep a cached copy
of current in another variable. This patch implements that for the
de_thread function.
(akpm: saves nearly 100 bytes of text on x86)
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] pid: remove temporary debug code in attach_pid
With the patches flying between Oleg and myself somehow this temporary
debug code got left in pid.c. It was never intended to make it to the
stable kernel.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] pid: Implement transfer_pid and use it to simplify de_thread
In de_thread we move pids from one process to another, a rather ugly case.
The function transfer_pid makes it clear what we are doing, and makes the
action atomic. This is useful we ever want to atomically traverse the
process group and session lists, in a rcu safe manner.
Even if the atomic properties this change should be a win as transfer_pid
should be less code to execute than executing both attach_pid and
detach_pid, and this should make de_thread slightly smaller as only a
single function call needs to be emitted. The only downside is that the
code might be slower to execute as the odds are against transfer_pid being
in cache.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] sysctl: Document that sys_sysctl will be removed
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] sysctl: Allow /proc/sys without sys_sysctl
Since sys_sysctl is deprecated start allow it to be compiled out. This
should catch any remaining user space code that cares, and paves the way
for further sysctl cleanups.
[akpm@osdl.org: If sys_sysctl() is not compiled-in, emit a warning] Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] Include __param section in read-only data range
The param section is an array of "kernel_param" structures, storing only
constant data: pointer to name, permission of the variable pointed to by
(void *)arg and pointers to set/get methods.
Move end_rodata down to include __param section in the read-only range used
by CONFIG_DEBUG_RODATA.
Signed-off-by: Marcelo Tosatti <marcelo@kvack.org> Acked-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Michael Tokarev [Wed, 27 Sep 2006 08:50:56 +0000 (01:50 -0700)]
[PATCH] EISA bus MODALIAS attributes support
Add modalias attribute support for the almost forgotten now EISA bus and
(at least some) EISA-aware modules.
The modalias entry looks like (for an 3c509 NIC):
eisa:sTCM5093
and the in-module alias like:
eisa:sTCM5093*
The patch moves struct eisa_device_id declaration from include/linux/eisa.h
to include/linux/mod_devicetable.h (so that the former now #includes the
latter), adds proper MODULE_DEVICE_TABLE(eisa, ...) statements for all
drivers with EISA IDs I found (some drivers already have that DEVICE_TABLE
declared), and adds recognision of __mod_eisa_device_table to
scripts/mod/file2alias.c so that proper modules.alias will be generated.
There's no support for /lib/modules/$kver/modules.eisamap, as it's not used
by any existing tools, and because with in-kernel modalias mechanism those
maps are obsolete anyway.
The rationale for this patch is:
a) to make EISA bus to act as other busses with modalias
support, to unify driver loading
b) to foget about EISA finally - with this patch, kernel
(who still supports EISA) will be the only one who knows
how to choose the necessary drivers for this bus ;)
[akpm@osdl.org: fix the kbuild bit] Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Randy Dunlap <rdunlap@xenotime.net> Acked-the-net-bits-by: Jeff Garzik <jeff@garzik.org> Acked-the-tulip-bit-by: Valerie Henson <val_henson@linux.intel.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Shaohua Li [Wed, 27 Sep 2006 08:50:54 +0000 (01:50 -0700)]
[PATCH] x86 microcode: don't check the size
IA32 manual says if micorcode update's size is 0, then the size is
default size (2048 bytes). But this doesn't suggest all microcode
update's size should be above 2048 bytes to me. We actually had a
microcode update whose size is 1024 bytes. The patch just removed the
check.
Signed-off-by: Shaohua Li <shaohua.li@intel.com> Cc: Tigran Aivazian <tigran@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Shaohua Li [Wed, 27 Sep 2006 08:50:53 +0000 (01:50 -0700)]
[PATCH] x86 microcode: add sysfs and hotplug support
Add sysfs support. Currently each CPU has three microcode related
attributes. One is 'version' which shows current ucode version of CPU.
Tools can use the attribute do validation or show CPU ucode status. one is
'reload' which allows manually reloading ucode. Another is
'processor_flags', which exports processor flags, so we can write tools to
check if CPU has latest ucode. Also add suspend/resume and CPU hotplug
support.
Shaohua Li [Wed, 27 Sep 2006 08:50:52 +0000 (01:50 -0700)]
[PATCH] x86 microcode: using request_firmware to pull microcode
Using request_firmware to pull ucode from userspace, so we don't need the
application 'microcode_ctl' to assist. We name each ucode file according
to CPU's info as intel-ucode/family-model-stepping. In this way we could
split ucode file as small one. This has a lot of advantages such as
selectively update and validate microcode for specific models, better
manage microcode file, easily write tools for administerators and so on.
with the changes, we should put all intel-ucode/xx-xx-xx microcode files
into the firmware dir (I had a tool to split previous big data file into
small one and later we will release new style data file). The init script
should be changed to just loading the driver without unloading
Signed-off-by: Shaohua Li <shaohua.li@intel.com> Acked-by: Tigran Aivazian <tigran@veritas.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Adrian Bunk [Wed, 27 Sep 2006 08:50:50 +0000 (01:50 -0700)]
[PATCH] reiserfs: warn about the useless nolargeio option
Since the nolargeio option no longer has any effect, print a warning
instead of setting a write-only variable.
Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Chris Mason <mason@suse.com> Cc: Hans Reiser <reiser@namesys.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
[PATCH] inode-diet: Eliminate i_blksize from the inode structure
This eliminates the i_blksize field from struct inode. Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.
Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.
[PATCH] inode_diet: Replace inode.u.generic_ip with inode.i_private
The following patches reduce the size of the VFS inode structure by 28 bytes
on a UP x86. (It would be more on an x86_64 system). This is a 10% reduction
in the inode size on a UP kernel that is configured in a production mode
(i.e., with no spinlock or other debugging functions enabled; if you want to
save memory taken up by in-core inodes, the first thing you should do is
disable the debugging options; they are responsible for a huge amount of bloat
in the VFS inode structure).
This patch:
The filesystem or device-specific pointer in the inode is inside a union,
which is pretty pointless given that all 30+ users of this field have been
using the void pointer. Get rid of the union and rename it to i_private, with
a comment to explain who is allowed to use the void pointer. This is just a
cleanup, but it allows us to reuse the union 'u' for something something where
the union will actually be used.
[PATCH] kdump: introduce "reset_devices" command line option
Resetting the devices during driver initialization can be a costly
operation in terms of time (especially scsi devices). This option can be
used by drivers to know that user forcibly wants the devices to be reset
during initialization.
This option can be useful while kernel is booting in unreliable
environment. For ex. during kdump boot where devices are in unknown
random state and BIOS execution has been skipped.
Ian Kent [Wed, 27 Sep 2006 08:50:44 +0000 (01:50 -0700)]
[PATCH] autofs4 needs to force fail return revalidate
For a long time now I have had a problem with not being able to return a
lookup failure on an existsing directory. In autofs this corresponds to a
mount failure on a autofs managed mount entry that is browsable (and so the
mount point directory exists).
While this problem has been present for a long time I've avoided resolving
it because it was not very visible. But now that autofs v5 has "mount and
expire on demand" of nested multiple mounts, such as is found when mounting
an export list from a server, solving the problem cannot be avoided any
longer.
I've tried very hard to find a way to do this entirely within the autofs4
module but have not been able to find a satisfactory way to achieve it.
So, I need to propose a change to the VFS.
Signed-off-by: Ian Kent <raven@themaw.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:42 +0000 (01:50 -0700)]
[PATCH] uml: fix sleep length bug
um_timer shouldn't add local_offset to the host time since get_time already
did it. This threw off sleep when a settimeofday or equivalent had happened.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:40 +0000 (01:50 -0700)]
[PATCH] uml: thread creation tidying
fork on UML has always somewhat subtle. The underlying cause has been the
need to initialize a stack for the new process. The only portable way to
initialize a new stack is to set it as the alternate signal stack and take a
signal. The signal handler does whatever initialization is needed and jumps
back to the original stack, where the fork processing is finished. The basic
context switching mechanism is a jmp_buf for each process. You switch to a
new process by longjmping to its jmp_buf.
Now that UML has its own implementation of setjmp and longjmp, and I can poke
around inside a jmp_buf without fear that libc will change the structure, a
much simpler mechanism is possible. The jmpbuf can simply be initialized by
hand.
This eliminates -
the need to set up and remove the alternate signal stack
sending and handling a signal
the signal blocking needed around the stack switching, since
there is no stack switching
setting up the jmp_buf needed to jump back to the original
stack after the new one is set up
In addition, since jmp_buf is now defined by UML, and not by libc, it can be
embedded in the thread struct. This makes it unnecessary to have it exist on
the stack, where it used to be. It also simplifies interfaces, since the
switch jmp_buf used to be a void * inside the thread struct, and functions
which took it as an argument needed to define a jmp_buf variable and assign it
from the void *.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:38 +0000 (01:50 -0700)]
[PATCH] uml: mark some tt-mode code
Mark a symbol and file as being tt-mode only. This shrinks the binary
slightly when tt mode support is compiled out and makes it easier to identity
stuff when tt mode is removed.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:37 +0000 (01:50 -0700)]
[PATCH] uml: add checkstack support
Make checkstack work for UML. We need to pass the underlying architecture
name, rather than "um" to checkstack.pl.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Acked-by: Matt Mackall <mpm@selenic.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:37 +0000 (01:50 -0700)]
[PATCH] uml: use correct SIGBUS handler
BB noticed that we had the wrong bus error handler.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:36 +0000 (01:50 -0700)]
[PATCH] uml: fix gcov support
Make __bb_init_func weak in order to avoid a link failure with some libcs
and/or gccs.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The UML/x86_64 headers were missing ptrace support for some segment registers.
The underlying problem was that the x86_64 kernel uses user_regs_struct
rather than the ptrace register definitions in ptrace. This patch switches
UML/x86_64 to using user_regs_struct for its definitions of the host's
registers.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:34 +0000 (01:50 -0700)]
[PATCH] uml: get rid of ZONE_DMA use
ZONE_DMA might become dependent on CONFIG_ZONE_DMA, which UML doesn't define
(we're still arguing about this) So, let's change ZONE_DMA to ZONE_NORMAL.
This is prompted by optional-zone_dma-in-the-vm.patch, but should be harmless
on its own.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Jeff Dike [Wed, 27 Sep 2006 08:50:33 +0000 (01:50 -0700)]
[PATCH] uml: const more data
Make lots of structures const in order to make it obvious that they need no
locking.
Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This spinlock can be taken on interrupt too, so spin_lock_irq[save] must be
used.
However, Documentation/networking/netdevices.txt explains we are called with
rtnl_lock() held - so we don't need to care about other concurrent opens.
Verified also in LDD3 and by direct checking. Also verified that the network
layer (through a state machine) guarantees us that nobody will close the
interface while it's being used. Please correct me if I'm wrong.
Also, we must check we don't sleep with irqs disabled!!! But anyway, this is
not news - we already can't sleep while holding a spinlock. Who says this is
guaranted really by the present code?
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Cc: Jeff Garzik <jeff@garzik.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We have never used this flag and recently one user experienced a complaining
warning about this (there was a symbol in the positive half of the address space
IIRC). So fix it.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
David Howells [Wed, 27 Sep 2006 08:50:23 +0000 (01:50 -0700)]
[PATCH] NOMMU: move the fallback arch_vma_name() to a sensible place
Move the fallback arch_vma_name() to a sensible place (kernel/signal.c).
Currently it's in fs/proc/task_mmu.c, a file that is dependent on both
CONFIG_PROC_FS and CONFIG_MMU being enabled, but it's used from
kernel/signal.c from where it is called unconditionally.
[akpm@osdl.org: build fix] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The first program will set up a SYSV IPC SHM segment and wait on a futex in it
for the number at the start to change. The program will increment that number
and wake the first program up. This leads to output of the form:
David Howells [Wed, 27 Sep 2006 08:50:21 +0000 (01:50 -0700)]
[PATCH] NOMMU: Make mremap() partially work for NOMMU kernels
Make mremap() partially work for NOMMU kernels. It may resize a VMA provided
that it doesn't exceed the size of the slab object in which the storage is
allocated that the VMA refers to. Shareable VMAs may not be resized.
Moving VMAs (as permitted by MREMAP_MAYMOVE) is not currently supported.
This patch also makes use of the fact that the VMA list is now ordered to cut
it short when possible.
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
David Howells [Wed, 27 Sep 2006 08:50:19 +0000 (01:50 -0700)]
[PATCH] NOMMU: Permit ptrace to ignore non-PROT_WRITE VMAs in NOMMU mode
Permit ptrace to modify a section that's non-shared but is marked
unwritable, such as is obtained by mapping the text segment of an ELF-FDPIC
executable binary with into a binary that's being ptraced[*].
[*] Under NOMMU conditions ptrace causes read-only MAP_PRIVATE mmaps to become
totally private copies because if a private mapping was actually shared
then the debugging setting breakpoints in it would potentially crash
other processes.
This is done by using the VM_MAYWRITE flag rather than the VM_WRITE flag
when deciding whether to permit a write.
Without this patch a debugger can't set breakpoints in the mapped text
sections of executables that are mapped read-only private, even if the
mmap() syscall has taken a private copy because PT_PTRACED is set.
In addition, VM_MAYREAD is used instead of VM_READ for similar reasons.
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Sonic Zhang [Wed, 27 Sep 2006 08:50:17 +0000 (01:50 -0700)]
[PATCH] Check if start address is in vma region in NOMMU function get_user_pages()
In NOMMU arch, if run "cat /proc/self/mem", data from physical address 0
are read. This behavior is different from MMU arch. In IA32, message
"cat: /proc/self/mem: Input/output error" is reported.
This issue is rootcaused by not validate the start address in NOMMU
function get_user_pages(). Following patch solves this issue.
Signed-off-by: Sonic Zhang <sonic.adi@gmail.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
David Howells [Wed, 27 Sep 2006 08:50:16 +0000 (01:50 -0700)]
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem
Set the backing device info capabilities for /dev/mem and /dev/kmem to
permit direct sharing under no-MMU conditions and full mapping capabilities
under MMU conditions. Make the BDI used by these available to all directly
mappable character devices.
Also comment the capabilities for /dev/zero.
[akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The empty line between the short description and the first argument
description causes a section to appear twice in the generated manpage.
Also the short description should really be short: the script can't handle
multiple lines.
Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Implement the special memory driver (mspec) based on the do_no_pfn
approach. The driver is currently used only on SN2 hardware with special
fetchop support but could be beneficial on other architectures using the
uncached mode.
Signed-off-by: Jes Sorensen <jes@sgi.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Implement do_no_pfn() for handling mapping of memory without a struct page
backing it. This avoids creating fake page table entries for regions which
are not backed by real memory.
This feature is used by the MSPEC driver and other users, where it is
highly undesirable to have a struct page sitting behind the page (for
instance if the page is accessed in cached mode via the struct page in
parallel to the the driver accessing it uncached, which can result in data
corruption on some architectures, such as ia64).
This version uses specific NOPFN_{SIGBUS,OOM} return values, rather than
expect all negative pfn values would be an error. It also bugs on cow
mappings as this would not work with the VM.
Signed-off-by: Christoph Lameter <clameter@sgi.com> Acked-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch insures that the slab node lists in the NUMA case only contain
slabs that belong to that specific node. All slab allocations use
GFP_THISNODE when calling into the page allocator. If an allocation fails
then we fall back in the slab allocator according to the zonelists appropriate
for a certain context.
This allows a replication of the behavior of alloc_pages and alloc_pages node
in the slab layer.
Currently allocations requested from the page allocator may be redirected via
cpusets to other nodes. This results in remote pages on nodelists and that in
turn results in interrupt latency issues during cache draining. Plus the slab
is handing out memory as local when it is really remote.
Fallback for slab memory allocations will occur within the slab allocator and
not in the page allocator. This is necessary in order to be able to use the
existing pools of objects on the nodes that we fall back to before adding more
pages to a slab.
The fallback function insures that the nodes we fall back to obey cpuset
restrictions of the current context. We do not allocate objects from outside
of the current cpuset context like before.
Note that the implementation of locality constraints within the slab allocator
requires importing logic from the page allocator. This is a mischmash that is
not that great. Other allocators (uncached allocator, vmalloc, huge pages)
face similar problems and have similar minimal reimplementations of the basic
fallback logic of the page allocator. There is another way of implementing a
slab by avoiding per node lists (see modular slab) but this wont work within
the existing slab.
V1->V2:
- Use NUMA_BUILD to avoid #ifdef CONFIG_NUMA
- Exploit GFP_THISNODE being 0 in the NON_NUMA case to avoid another
#ifdef
[akpm@osdl.org: build fix] Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>