sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we
need two atomic operations (and associated dirtying) per incoming
packet.
RCU conversion is pretty much needed :
1) Add a new structure, called "struct socket_wq" to hold all fields
that will need rcu_read_lock() protection (currently: a
wait_queue_head_t and a struct fasync_struct pointer).
[Future patch will add a list anchor for wakeup coalescing]
2) Attach one of such structure to each "struct socket" created in
sock_alloc_inode().
3) Respect RCU grace period when freeing a "struct socket_wq"
4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct
socket_wq"
5) Change sk_sleep() function to use new sk->sk_wq instead of
sk->sk_sleep
6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside
a rcu_read_lock() section.
7) Change all sk_has_sleeper() callers to :
- Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock)
- Use wq_has_sleeper() to eventually wakeup tasks.
- Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock)
8) sock_wake_async() is modified to use rcu protection as well.
9) Exceptions :
macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq"
instead of dynamically allocated ones. They dont need rcu freeing.
Some cleanups or followups are probably needed, (possible
sk_callback_lock conversion to a spinlock for example...).
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
blk_abort_request() expects queue lock to be held by the caller.
Grab it before calling the function.
Lack of this synchronization led to infinite loop on corrupt
q->timeout_list.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch fixes sdev_rw_attr() macro for scsi device sysfs entries.
It seems there is no such function snscanf in the current linux kernel,
so it fails to compile scsi driver when someone try to add a new rw entry.
This has been unfixed for a long time probably because current scsi device
has no rw entries.
# grep snscanf . -rn
./drivers/scsi/scsi_sysfs.c:489: snscanf (buf, 20, format_string, &sdev->field); \
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@jp.fujitsu.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Fix the compilation warning in powerpc. The same change also fixes endian
issue we found in powerpc test. This patch has been tested in x86 and
powerpc platform. it is created using scsi-misc-2.6.
Signed-off-by: Jing Huang <huangj@brocade.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Fix a number of RCU issues in the NFSv4 delegation code.
(1) delegation->cred doesn't need to be RCU protected as it's essentially an
invariant refcounted structure.
By the time we get to nfs_free_delegation(), the delegation is being
released, so no one else should be attempting to use the saved
credentials, and they can be cleared.
However, since the list of delegations could still be under traversal at
this point by such as nfs_client_return_marked_delegations(), the cred
should be released in nfs_do_free_delegation() rather than in
nfs_free_delegation(). Simply using rcu_assign_pointer() to clear it is
insufficient as that doesn't stop the cred from being destroyed, and nor
does calling put_rpccred() after call_rcu(), given that the latter is
asynchronous.
(2) nfs_detach_delegation_locked() and nfs_inode_set_delegation() should use
rcu_derefence_protected() because they can only be called if
nfs_client::cl_lock is held, and that guards against anyone changing
nfsi->delegation under it. Furthermore, the barrier imposed by
rcu_dereference() is superfluous, given that the spin_lock() is also a
barrier.
(3) nfs_detach_delegation_locked() is now passed a pointer to the nfs_client
struct so that it can issue lockdep advice based on clp->cl_lock for (2).
(4) nfs_inode_return_delegation_noreclaim() and nfs_inode_return_delegation()
should use rcu_access_pointer() outside the spinlocked region as they
merely examine the pointer and don't follow it, thus rendering unnecessary
the need to impose a partial ordering over the one item of interest.
These result in an RCU warning like the following:
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
fs/nfs/delegation.c:332 invoked rcu_dereference_check() without protection!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
2 locks held by mount.nfs4/2281:
#0: (&type->s_umount_key#34){+.+...}, at: [<ffffffff810b25b4>] deactivate_super+0x60/0x80
#1: (iprune_sem){+.+...}, at: [<ffffffff810c332a>] invalidate_inodes+0x39/0x13a
stack backtrace:
Pid: 2281, comm: mount.nfs4 Not tainted 2.6.34-rc1-cachefs #110
Call Trace:
[<ffffffff8105149f>] lockdep_rcu_dereference+0xaa/0xb2
[<ffffffffa00b4591>] nfs_inode_return_delegation_noreclaim+0x5b/0xa0 [nfs]
[<ffffffffa0095d63>] nfs4_clear_inode+0x11/0x1e [nfs]
[<ffffffff810c2d92>] clear_inode+0x9e/0xf8
[<ffffffff810c3028>] dispose_list+0x67/0x10e
[<ffffffff810c340d>] invalidate_inodes+0x11c/0x13a
[<ffffffff810b1dc1>] generic_shutdown_super+0x42/0xf4
[<ffffffff810b1ebe>] kill_anon_super+0x11/0x4f
[<ffffffffa009893c>] nfs4_kill_super+0x3f/0x72 [nfs]
[<ffffffff810b25bc>] deactivate_super+0x68/0x80
[<ffffffff810c6744>] mntput_no_expire+0xbb/0xf8
[<ffffffff810c681b>] release_mounts+0x9a/0xb0
[<ffffffff810c689b>] put_mnt_ns+0x6a/0x79
[<ffffffffa00983a1>] nfs_follow_remote_path+0x5a/0x146 [nfs]
[<ffffffffa0098334>] ? nfs_do_root_mount+0x82/0x95 [nfs]
[<ffffffffa00985a9>] nfs4_try_mount+0x75/0xaf [nfs]
[<ffffffffa0098874>] nfs4_get_sb+0x291/0x31a [nfs]
[<ffffffff810b2059>] vfs_kern_mount+0xb8/0x177
[<ffffffff810b2176>] do_kern_mount+0x48/0xe8
[<ffffffff810c810b>] do_mount+0x782/0x7f9
[<ffffffff810c8205>] sys_mount+0x83/0xbe
[<ffffffff81001eeb>] system_call_fastpath+0x16/0x1b
Also on:
fs/nfs/delegation.c:215 invoked rcu_dereference_check() without protection!
[<ffffffff8105149f>] lockdep_rcu_dereference+0xaa/0xb2
[<ffffffffa00b4223>] nfs_inode_set_delegation+0xfe/0x219 [nfs]
[<ffffffffa00a9c6f>] nfs4_opendata_to_nfs4_state+0x2c2/0x30d [nfs]
[<ffffffffa00aa15d>] nfs4_do_open+0x2a6/0x3a6 [nfs]
...
And:
fs/nfs/delegation.c:40 invoked rcu_dereference_check() without protection!
[<ffffffff8105149f>] lockdep_rcu_dereference+0xaa/0xb2
[<ffffffffa00b3bef>] nfs_free_delegation+0x3d/0x6e [nfs]
[<ffffffffa00b3e71>] nfs_do_return_delegation+0x26/0x30 [nfs]
[<ffffffffa00b406a>] __nfs_inode_return_delegation+0x1ef/0x1fe [nfs]
[<ffffffffa00b448a>] nfs_client_return_marked_delegations+0xc9/0x124 [nfs]
...
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we correctly rcu-dereference the delegation itself, and that we
protect against removal while we're changing the contents.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
logfs_seek_hole() may return the same offset it is passed as argument.
Found by Prasad Joshi <prasadjoshi124@gmail.com>
Signed-off-by: Joern Engel <joern@logfs.org>
Error handling on advansys_board_found is fixed, because it's buggy in
the case we have an ASC_NARROW_BOARD set and failure happens on
AscInitAsc1000Driver step: it was freeing items of wrong struct in the
dvc_var union of struct asc_board, which could lead to an oops in the
case we set some of the fields in struct of narrow board as code was
choosing to always freeing wide board fields, and not everything was
being freed/released properly.
Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
iop32x_defconfig:
In file included from include/linux/elf.h:7,
from kernel/elfcore.c:1:
arch/arm/include/asm/elf.h:101: warning: "struct task_struct" declared inside parameter list
arch/arm/include/asm/elf.h:101: warning: its scope is only this definition or declaration, which is probably not what you want
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Test the just-allocated value for NULL rather than some other value.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression x,y;
statement S;
@@
x = \(kmalloc\|kcalloc\|kzalloc\)(...);
(
if ((x) == NULL) S
|
if (
- y
+ x
== NULL)
S
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Just to make sure that this driver won't run on StrongArm SA1100
when both SA1100 and SA1110 cpufreq drivers are built in (usually
in multimachine config). SA1100 driver already has similar check.
Signed-off-by: Dmitry Artamonow <mad_soft@inbox.ru>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Acked-by: Kristoffer Ericson <kristoffer.ericson@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes the preempt leak in the cpuidle path invoked from
cpu-hotplug. The fix is suggested by Russell King and is based
on x86 idea of calling init_idle() on the idle task when it's
re-used which also resets the preempt count amongst other things
dump:
BUG: scheduling while atomic: swapper/0/0x00000002
Modules linked in:
Backtrace:
[<c0024f90>] (dump_backtrace+0x0/0x110) from [<c0173bc4>] (dump_stack+0x18/0x1c)
r7:c02149e4 r6:c033df00 r5:c7836000 r4:00000000
[<c0173bac>] (dump_stack+0x0/0x1c) from [<c003b4f0>] (__schedule_bug+0x60/0x70)
[<c003b490>] (__schedule_bug+0x0/0x70) from [<c0174214>] (schedule+0x98/0x7b8)
r5:c7836000 r4:c7836000
[<c017417c>] (schedule+0x0/0x7b8) from [<c00228c4>] (cpu_idle+0xb4/0xd4)
# [<c0022810>] (cpu_idle+0x0/0xd4) from [<c0171dd8>] (secondary_start_kernel+0xe0/0xf0)
r5:c7836000 r4:c0205f40
[<c0171cf8>] (secondary_start_kernel+0x0/0xf0) from [<c002d57c>] (prm_rmw_mod_reg_bits+0x88/0xa4)
r7:c02149e4 r6:00000001 r5:00000001 r4:c7836000
Backtrace aborted due to bad frame pointer <c7837fbc>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With CONFIG_KPROBES enabled two section are getting created which
leads to below build break.
LOG:
AS arch/arm/kernel/entry-armv.o
arch/arm/kernel/entry-armv.S: Assembler messages:
arch/arm/kernel/entry-armv.S:431: Error: symbol ret_from_exception is in a different section
arch/arm/kernel/entry-armv.S:490: Error: symbol ret_from_exception is in a different section
arch/arm/kernel/entry-armv.S:491: Error: symbol __und_usr_unknown is in a different section
This was introduced by commit 4260415f6a
Reported-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Implement an alternate percpu chunk management based on kernel memeory
for nommu SMP architectures. Instead of mapping into vmalloc area,
chunks are allocated as a contiguous kernel memory using
alloc_pages(). As such, percpu allocator on nommu will have the
following restrictions.
* It can't fill chunks on-demand page-by-page. It has to allocate
each chunk fully upfront.
* It can't support sparse chunk for NUMA configurations. SMP w/o mmu
is crazy enough. Let's hope no one does NUMA w/o mmu. :-P
* If chunk size isn't power-of-two multiple of PAGE_SIZE, the
unaligned amount will be wasted on each chunk. So, archs which use
this better align chunk size.
For instructions on how to use this, read the comment on top of
mm/percpu-km.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: Graff Yang <graff.yang@gmail.com>
Cc: Sonic Zhang <sonic.adi@gmail.com>
Separate out and move chunk management (creation/desctruction and
[de]population) code into percpu-vm.c which is included by percpu.c
and compiled together. The interface for chunk management is defined
as follows.
* pcpu_populate_chunk - populate the specified range of a chunk
* pcpu_depopulate_chunk - depopulate the specified range of a chunk
* pcpu_create_chunk - create a new chunk
* pcpu_destroy_chunk - destroy a chunk, always preceded by full depop
* pcpu_addr_to_page - translate address to physical address
* pcpu_verify_alloc_info - check alloc_info is acceptable during init
Other than wrapping vmalloc_to_page() inside pcpu_addr_to_page() and
dummy pcpu_verify_alloc_info() implementation, this patch only moves
code around. This separation is to allow alternate chunk management
implementation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: Graff Yang <graff.yang@gmail.com>
Cc: Sonic Zhang <sonic.adi@gmail.com>
Make the following misc preparations for percpu nommu support.
* Remove refernces to vmalloc in common comments as nommu percpu won't
use it.
* Rename chunk->vms to chunk->data and make it void *. Its use is
determined by chunk management implementation.
* Relocate utility functions and add __maybe_unused to functions which
might not be used by different chunk management implementations.
This patch doesn't cause any functional change. This is to allow
alternate chunk management implementation for percpu nommu support.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: Graff Yang <graff.yang@gmail.com>
Cc: Sonic Zhang <sonic.adi@gmail.com>
Reorganize alloc/free_pcpu_chunk() such that chunk struct alloc/free
live in pcpu_alloc/free_chunk() and the rest in
pcpu_create/destroy_chunk(). While at it, add missing error handling
for chunk->map allocation failure.
This is to allow alternate chunk management implementation for percpu
nommu support.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: Graff Yang <graff.yang@gmail.com>
Cc: Sonic Zhang <sonic.adi@gmail.com>
Factor out pcpu_addr_in_first/reserved_chunk() from
pcpu_chunk_addr_search() and use it to update per_cpu_ptr_to_phys()
such that it handles first chunk differently from the rest.
This patch doesn't cause any functional change and is to prepare for
percpu nommu support.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: Graff Yang <graff.yang@gmail.com>
Cc: Sonic Zhang <sonic.adi@gmail.com>
When we create the sctp_datamsg and fragment the user data,
we know exactly if we are sending full segments or not and
how they might be bundled. During this time, we can mark
messages a Nagle capable or not. This makes the check at
transmit time much simpler.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Right now, if the highest tsn in the SACK doesn't change, we'll
end up scanning the transmitted lists on the transports twice:
once for locating the highest _new_ tsn, and once for actually
tagging chunks as acked. This is a waste, since we can record
the highest _new_ tsn at the same time as tagging chunks. Long
ago this was not possible because we would try to mark chunks
as missing at the same time as tagging them acked and this approach
didn't work. Now that the two steps are separate, we can re-use
the old approach.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
According to RFC 4960 Section 7.2.4:
If an endpoint is in Fast
Recovery and a SACK arrives that advances the Cumulative TSN Ack
Point, the miss indications are incremented for all TSNs reported
missing in the SACK.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
rwnd_press tracks the pressure on the recieve window. Every
timer the receive buffer overlows, we truncate the receive
window and then grow it back. However, if we don't track
the cumulative presser, it's possible to reach a situation
when receive buffer is empty, but rwnd stays truncated.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Right now, sctp transports are not fully initialized and when
adding any new fields, they have to be explicitely initialized.
This is prone to mistakes. So we switch to calling kzalloc()
which makes things much simpler.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
We don't need to force the T3 timer any more and it's
actually wrong to do as it causes too long of a delay.
The timer will be started if one is not running, but if
one is running, we leave it alone.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
The 'resent' bit is used to make sure that we don't update
rto estimate based on retransmitted chunks. However, we already
have the 'rto_pending' bit that we test when need to update rto,
so 'resent' bit is just extra. Additionally, we currently have
a bug in that we always set a 'resent' bit and thus rto estimate
is only updated by Heartbeats.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
commit 4951feda0c60d1ef681f1a270afdd617924ab041
sctp: Do no select unconfirmed transports for retransmissions
added code to make sure that we do not select unconfirmed paths
for data transmission. This caused a problem when there are only
2 paths, 1 unconfirmed and 1 unreachable. In that case, the next
retransmit path returned is NULL and that causes a kernel crash.
The solution is to only change retransmit paths if we found one to use.
Reported-by: Frank Schuster <frank.schuster01@web.de>
Signed-off-b: Vlad Yasevich <vladislav.yasevich@hp.com>
This assignment isn't needed because we did it earlier already.
Also another reason to delete the assignment is because it triggers a
Smatch warning about checking for NULL pointers after a dereference.
Reported-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
This patch implement sctp association probing module, the module
will be called sctp_probe.
This module allows for capturing the changes to SCTP association
state in response to incoming packets. It is used for debugging
SCTP congestion control algorithms.
Usage:
$ modprobe sctp_probe [full=n] [port=n] [bufsize=n]
$ cat /proc/net/sctpprobe
The output format is:
TIME ASSOC LPORT RPORT MTU RWND UNACK <REMOTE-ADDR STATE CWND SSTHRESH INFLIGHT PARTIAL_BYTES_ACKED MTU> ...
The output will be like this:
9.226086 c4064c48 9000 8000 1500 53352 1 *192.168.0.19 1 4380 54784 1252 0 1500
9.287195 c4064c48 9000 8000 1500 45144 5 *192.168.0.19 1 5880 54784 6500 0 1500
9.289130 c4064c48 9000 8000 1500 42724 5 *192.168.0.19 1 7380 54784 6500 0 1500
9.620332 c4064c48 9000 8000 1500 48284 4 *192.168.0.19 1 8880 54784 5200 0 1500
......
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
sctp_chunk_is_data macro is defined to decide that
whether a chunk is data chunk or not.
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
An unconfirmed transport is one that we have not been
able to reach since the beginning. There is no point in
trying to retrasnmit data on those transports. Also, the
specification forbids it due to security issues.
Reported-by: Frank Schuster <frank.schuster01@web.de>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
While doing retranmit, if control chunk exists, such as
FORWARD TSN chunk, and the DATA chunk can not be bundled with
this control chunk because of PMTU limit, no DATA chunk
will be retranmitted in the current implementation. This
patch makes sure to retranmit at least one DATA chunk in this case.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
The breakpoint generic layer assumes that archs always know in advance
the static number of address registers available to host breakpoints
through the HBP_NUM macro.
However this is not true for every archs. For example Arm needs to get
this information dynamically to handle the compatiblity between
different versions.
To solve this, this patch proposes to drop the static HBP_NUM macro
and let the arch provide the number of available slots through a
new hw_breakpoint_slots() function. For archs that have
CONFIG_HAVE_MIXED_BREAKPOINTS_REGS selected, it will be called once
as the number of registers fits for instruction and data breakpoints
together.
For the others it will be called first to get the number of
instruction breakpoint registers and another time to get the
data breakpoint registers, the targeted type is given as a
parameter of hw_breakpoint_slots().
Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: K. Prasad <prasad@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Depending on their nature and on what an arch supports, breakpoints
may consume more than one address register. For example a simple
absolute address match usually only requires one address register.
But an address range match may consume two registers.
Currently our slot allocation constraints, that tend to reflect the
limited arch's resources, always consider that a breakpoint consumes
one slot.
Then provide a way for archs to tell us the weight of a breakpoint
through a new hw_breakpoint_weight() helper. This weight will be
computed against the generic allocation constraints instead of
a constant value.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: K. Prasad <prasad@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
There are two outstanding fashions for archs to implement hardware
breakpoints.
The first is to separate breakpoint address pattern definition
space between data and instruction breakpoints. We then have
typically distinct instruction address breakpoint registers
and data address breakpoint registers, delivered with
separate control registers for data and instruction breakpoints
as well. This is the case of PowerPc and ARM for example.
The second consists in having merged breakpoint address space
definition between data and instruction breakpoint. Address
registers can host either instruction or data address and
the access mode for the breakpoint is defined in a control
register. This is the case of x86 and Super H.
This patch adds a new CONFIG_HAVE_MIXED_BREAKPOINTS_REGS config
that archs can select if they belong to the second case. Those
will have their slot allocation merged for instructions and
data breakpoints.
The others will have a separate slot tracking between data and
instruction breakpoints.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: K. Prasad <prasad@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
The current policies of breakpoints in x86 and SH are the following:
- task bound breakpoints can only break on userspace addresses
- cpu wide breakpoints can only break on kernel addresses
The former rule prevents ptrace breakpoints to be set to trigger on
kernel addresses, which is good. But as a side effect, we can't
breakpoint on kernel addresses for task bound breakpoints.
The latter rule simply makes no sense, there is no reason why we
can't set breakpoints on userspace while performing cpu bound
profiles.
We want the following new policies:
- task bound breakpoint can set userspace address breakpoints, with
no particular privilege required.
- task bound breakpoints can set kernelspace address breakpoints but
must be privileged to do that.
- cpu bound breakpoints can do what they want as they are privileged
already.
To implement these new policies, this patch checks if we are dealing
with a kernel address breakpoint, if so and if the exclude_kernel
parameter is set, we tell the user that the breakpoint is invalid,
which makes a good generic ptrace protection.
If we don't have exclude_kernel, ensure the user has the right
privileges as kernel breakpoints are quite sensitive (risk of
trap recursion attacks and global performance impacts).
[ Paul Mundt: keep addr space check for sh signal delivery and fix
double function declaration]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: K. Prasad <prasad@linux.vnet.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
commit e9e94e3bd8
"perf trace: Ignore "overwrite" field if present in
/events/header_page" makes perf trace launching spurious warnings
about unexpected tokens read:
Warning: Error: expected type 6 but read 4
This change tries to handle the overcommit field in the header_page
file whenever this field is present or not.
The problem is that if this field is not present, we try to find it
and give up in the middle of the line when we realize we are actually
dealing with another field, which is the "data" one. And this failure
abandons the file pointer in the middle of the "data" description
line:
field: u64 timestamp; offset:0; size:8; signed:0;
field: local_t commit; offset:8; size:8; signed:1;
field: char data; offset:16; size:4080; signed:1;
^^^
Here
What happens next is that we want to read this line to parse the data
field, but we fail because the pointer is not in the beginning of the
line.
We could probably fix that by rewinding the pointer. But in fact we
don't care much about these headers that only concern the ftrace
ring-buffer. We don't use them from perf.
Just skip this part of perf.data, but don't remove it from recording
to stay compatible with olders perf.data
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
While lookup the output route, we do not set the src and dest
port. This will cause we got a wrong route if we had set the
outbund transport to IPsec with src or dst port.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
