I recently stumbled upon a problem in the support for huge pages. If a
program using huge pages does not explicitly unmap them, they remain
mapped (and therefore, are lost) after the program exits.
I observed that the free huge page count in /proc/meminfo decreased when
running my program, and it did not increase after the program exited.
After running the program a few times, no more huge pages could be
allocated.
The reason for this seems to be that the x86 pmd_bad and pud_bad
consider pmd/pud entries having the PSE bit set invalid. I think there
is nothing wrong with this bit being set, it just indicates that the
lowest level of translation has been reached. This bit has to be (and
is) checked after the basic validity of the entry has been checked, like
in this fragment from follow_page() in mm/memory.c:
if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
goto no_page_table;
if (pmd_huge(*pmd)) {
BUG_ON(flags & FOLL_GET);
page = follow_huge_pmd(mm, address, pmd, flags & FOLL_WRITE);
goto out;
}
Note that this code currently doesn't work as intended if the pmd refers
to a huge page, the pmd_huge() check can not be reached if the page is
huge.
Extending pmd_bad() (and, for future 1GB page support, pud_bad()) to
allow for the PSE bit being set fixes this. For similar reasons,
allowing the NX bit being set is necessary, too. I have seen huge pages
having the NX bit set in their pmd entry, which would cause the same
problem.
Signed-Off-By: Hans Rosenfeld <hans.rosenfeld@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The PREEMPT-RCU can get stuck if a CPU goes idle and NO_HZ is set. The
idle CPU will not progress the RCU through its grace period and a
synchronize_rcu my get stuck. Without this patch I have a box that will
not boot when PREEMPT_RCU and NO_HZ are set. That same box boots fine
with this patch.
This patch comes from the -rt kernel where it has been tested for
several months.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/blackfin-2.6: (35 commits)
Blackfin Serial Driver: Fix bug - Only insert UART rx char in timer task.
Blackfin Serial Driver: Fix bug - update tx dma buffer tail before wake up processes.
Blackfin Serial Driver: Fix bug - Increase buffer tail immediately before starting tx dma.
[Blackfin] serial driver: Add flow control support to bf54x
[Blackfin] serial driver: Fix bug Poll RTS/CTS status in DMA mode as well
[Blackfin] serial driver: ADSP-BF52x arch/mach support
[Blackfin] serial driver: use simpler comment headers and strip out information that is maintained in the scm's log
[Blackfin] serial driver: rework break flood anomaly handling to be more robust/realistic about what we can actually work around
[Blackfin] serial driver: fix bug - cache the bits of the LSR on systems where the LSR is read-to-clear
[Blackfin] serial driver: fix bug - should not wait for the TFI bit, just clear it when tx stop.
[Blackfin] serial driver: Fix bug serial driver in DMA mode spams history to console on shell restart
[Blackfin] serial driver: Fix bug Free rx dma buffer in shutdown.
[Blackfin] serial driver: Clean up UART DMA code.
Blackfin Serial driver: Fix bug - serial driver in PIO mode cant handle input very quickly
[Blackfin] arch: kill section mismatch warnings
[Blackfin] arch: handle the most common L1 shrinkage case (L1 does not exist for a part) so that any parts labeled for L1 instead get placed into external memory sections
[Blackfin] arch: add bfin_clear_PPIx_STATUS() helper funcs like we have for other parts
[Blackfin] arch: make sure we have proper description/copyright/license lines
[Blackfin] arch: Fix CONFIG_PM support for BF561
[Blackfin] arch: Remove DPMC char driver option
...
This removes code duplication and makes __dec_zone_page_state look like
__inc_zone_page_state.
Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
arch/sh/drivers/dma/dma-sh.c: Correct use of ! and &
serial: Move asm-sh/sci.h to linux/serial_sci.h.
sh: Fix up HAS_SR_RB typo in entry-macros.
maple: fix device detection
sh: fix rtc_resources setup for sh770x
sh: heartbeat: ioremap is expected to succeed
sh: Storage class should be before const qualifier
maple: remove unused variable
sh: SH5-103 needs to select CPU_SH5.
sh: Rename SH-3 CCR3 reg to avoid synclink_cs clash.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (79 commits)
[X25]: Use proc_create() to setup ->proc_fops first
[WANROUTER]: Use proc_create() to setup ->proc_fops first
[8021Q]: Use proc_create() to setup ->proc_fops first
[IPV4]: Use proc_create() to setup ->proc_fops first
[IPV6]: Use proc_create() to setup ->proc_fops first
[SCTP]: Use proc_create() to setup ->proc_fops first
[PKTGEN]: Use proc_create() to setup ->proc_fops first
[NEIGHBOUR]: Use proc_create() to setup ->proc_fops first
[LLC]: Use proc_create() to setup ->proc_fops first
[IPX]: Use proc_create() to setup ->proc_fops first
[SUNRPC]: Use proc_create() to setup ->proc_fops first
[ATM]: Use proc_create() to setup ->proc_fops first
[SCTP]: Update AUTH structures to match declarations in draft-16.
[SCTP]: Incorrect length was used in SCTP_*_AUTH_CHUNKS socket option
[SCTP]: Clean up naming conventions of sctp protocol/address family registration
[APPLETALK]: Use proc_create() to setup ->proc_fops first
[BNX2X]: add bnx2x to MAINTAINERS
[BNX2X]: update version, remove CVS strings
[BNX2X]: Fix Xmit bugs
[BNX2X]: Prevent PCI queue overflow
...
I overlooked the difference between __kernel_uid_t and uid_t when defining
struct compat_elf_prpsinfo. The result is a regression in 32-bit core
dumps on x86_64, where the NT_PRPSINFO note has the wrong size and layout.
This patch fixes it.
Signed-off-by: Roland McGrath <roland@redhat.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that we've tightened up the locking rules for RPC queue wakeups, we can
remove the RCU-safe kfree calls...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is designed to replace the timeout timer in the individual rpc_tasks.
By putting the timer function in the wait queue, we will eventually be able
to reduce the total number of timers in use by the RPC subsystem.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Change xfrm_policy and xfrm_state walking algorithm from O(n^2) to O(n).
This is achieved adding the entries to one more list which is used
solely for walking the entries.
This also fixes some races where the dump can have duplicate or missing
entries when the SPD/SADB is modified during an ongoing dump.
Dumping SADB with 20000 entries using "time ip xfrm state" the sys
time dropped from 1.012s to 0.080s.
Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Skip the prefix length matching in source address selection for
orchid -> non-orchid addresses.
Overlay Routable Cryptographic Hash IDentifiers (RFC 4843,
2001:10::/28) are currenty not globally reachable. Without this
check a host with an ORCHID address can end up preferring those over
regular addresses when talking to other regular hosts in the 2001::/16
range thus breaking non-orchid connections.
Signed-off-by: Juha-Matti Tapio <jmtapio@verkkotelakka.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add namespace parameter to devinet_ioctl and locate device inside it for
state changes.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
- add platform device resources in board files
- add new bfin_sir.h to each machines
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
If the new value written to the PLL_CTL or VR_CTL register is the
same as the previous value, the PLL wake-up will occur immediately
(PLL is already locked), but the core and system clock will be
bypassed for the PLL_LOCKCNT duration. For this interval, code will
execute at the CLKIN rate instead of at the expected CCLK rate.
Software should guard against this condition by comparing the
current value to the new value before writing the new value.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The DMA base registers are available in a global named "base_addr" for
every Blackfin variant. Give this a more descriptive name, and remove
duplicate tables from some drivers.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
remove duplicated prototypes for internal cplb structures from
the global blackfin header as nothing else should be accessing these
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Previously, init failed to do anything meaningful;
it turns out that the reason is that FD-PIC has a readonly data
section which can be located in the XIP filesystem, and various address checks
in the kernel reject such addresses for syscall arguments. Hence, init's
execve ("/bin/sh", ...)
failed with error code EFAULT.
There's room for improvement here: in case people want to have filesystems
on flash rather than in main memory, _access_ok should be modified to
allow this.
This bug fix is also dedicated to Michael Hennerich.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
relocate MAX_SWITCH_{D,I}_CPLBS from the header to the file
where it actually gets used. this way when we change
CONFIG_MEM_SIZE in our kconfig, we only rebuild one or two files
rather than a whole bunch that implicitly include cplb.h.
this will also remove the ability to clear the swapcount on
the fly, but i really dont think that functionality is important.
ultimate goal is for CONFIG_MEM_SIZE to go away and calculate
this value on the fly based on what u-boot programmed for us.
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
replace implied numbers with real values so that strace is able to
calculate things automatically ... the numbers are frozen in our ABI,
so having them based off other __NR_xxx values really doesnt matter
-- no functional changes
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
There were a couple of problems with the way the trace buffer state
is saved/restored in assembly. The DEBUG_HWTRACE_SAVE/RESTORE macros
save a value to the stack, which is not immediately obvious; the CPLB
exception code needed changes to load the correct value of the stack
pointer. The other problem is that the SAVE/RESTORE macros weren't
pushing and popping the value downwards on the stack, but rather moving
it _upwards_, which is of course completely broken.
We also need to make sure there's a matching DEBUG_HWTRACE_RESTORE in
the error case of the CPLB handler.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The new SCTP socket api (draft 16) updates the AUTH API structures.
We never exported these since we knew they would change.
Update the rest to match the draft.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Properly add parens around the macro argument. This is not needed by
the kernel but the macro is exported to userspace, so it shouldn't
make any assumptions.
Also use NF_VERDICT_BITS instead of NF_VERDICT_QBTIS for the left-shift
since thats whats logically correct.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: add missing ext4_journal_stop()
ext4: ext4_find_next_zero_bit needs an aligned address on some arch
ext4: set EXT4_EXTENTS_FL only for directory and regular files
ext4: Don't mark filesystem error if fallocate fails
ext4: Fix BUG when writing to an unitialized extent
ext4: Don't use ext4_dec_count() if not needed
ext4: modify block allocation algorithm for the last group
ext4: Don't claim block from group which has corrupt bitmap
ext4: Get journal write access before modifying the extent tree
ext4: Fix memory and buffer head leak in callers to ext4_ext_find_extent()
ext4: Don't leave behind a half-created inode if ext4_mkdir() fails
ext4: Fix kernel BUG at fs/ext4/mballoc.c:910!
ext4: Fix locking hierarchy violation in ext4_fallocate()
Remove incorrect BKL comments in ext4
