These devices have a number of non serial interfaces as well. Use
the existing "Direct IP" blacklist to prevent binding to interfaces
which are handled by other drivers.
We also extend the "Direct IP" blacklist with with interfaces only
seen in "QMI" mode, assuming that these devices use the same
interface numbers for serial interfaces both in "Direct IP" and in
"QMI" mode.
This driver anticipates pch_uart_verify_port() is not called
during installation.
However, actually pch_uart_verify_port() is called during
installation.
As a result, memory access violation occurs like below.
0. initial value: use_dma=0
1. starup()
- dma channel is not allocated because use_dma=0
2. pch_uart_verify_port()
- Set use_dma=1
3. UART processing acts DMA mode because use_dma=1
- memory access violation occurs!
This patch fixes the issue.
Solution:
Whenever pch_uart_verify_port() is called and then
dma channel is not allocated, the channel should be allocated.
Fixed too small hardcoded timeout values for usb_control_msg
in driver for SiliconLabs cp210x-based usb-to-serial adapters.
Replaced with USB_CTRL_GET_TIMEOUT/USB_CTRL_SET_TIMEOUT.
flush request is issued in transaction commit code path, so looks using
GFP_KERNEL to allocate memory for flush request bio falls into the classic
deadlock issue. I saw btrfs and dm get it right, but ext4, xfs and md are
using GFP.
Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mel reports a BUG_ON(slot == NULL) in radix_tree_tag_set() on s390
3.0.13: called from __set_page_dirty_nobuffers() when page_remove_rmap()
tries to transfer dirty flag from s390 storage key to struct page and
radix_tree.
That would be because of reclaim's shrink_page_list() calling
add_to_swap() on this page at the same time: first PageSwapCache is set
(causing page_mapping(page) to appear as &swapper_space), then
page->private set, then tree_lock taken, then page inserted into
radix_tree - so there's an interval before taking the lock when the
radix_tree slot is empty.
We could fix this by moving __add_to_swap_cache()'s spin_lock_irq up
before the SetPageSwapCache. But a better fix is simply to do what's
five years overdue: Ken Chen introduced __set_page_dirty_no_writeback()
(if !PageDirty TestSetPageDirty) for tmpfs to skip all the radix_tree
overhead, and swap is just the same - it ignores the radix_tree tag, and
does not participate in dirty page accounting, so should be using
__set_page_dirty_no_writeback() too.
s390 testing now confirms that this does indeed fix the problem.
Under heavy load (flood ping) it is possible for the MDIO timeout to
expire before the loop checks the GO bit again. This patch adds an
additional check whether the operation was done before actually
returning -ETIMEDOUT.
To reproduce this bug, flood ping the device, e.g., ping -f -l 1000
After some time, a "timed out waiting for user access" warning
may appear. And even worse, link may go down since the PHY reported a
timeout.
Signed-off-by: Christian Riesch <christian.riesch@omicron.at> Cc: Cyril Chemparathy <cyril@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current probing code is setting URB_NO_TRANSFER_DMA_MAP flag into a wrong urb
structure, and this causes BUG_ON with some USB host implementations.
This patch fixes the issue.
Removes allocation of coherent buffer for the control-request setup-packet
buffer from the yurex driver. Using coherent buffers for setup-packet is
obsolete and does not work with some USB host implementations.
A rather annoying and common case is when booting a PVonHVM guest
and exposing the PV KBD and PV VFB - as broken toolstacks don't
always initialize the backends correctly.
Normally The HVM guest is using the VGA driver and the emulated
keyboard for this (though upstream version of QEMU implements
PV KBD, but still uses a VGA driver). We provide a very basic
two-stage wait mechanism - where we wait for 30 seconds for all
devices, and then for 270 for all them except the two mentioned.
That allows us to wait for the essential devices, like network
or disk for the full 6 minutes.
To trigger this, put this in your guest config:
vfb = [ 'vnc=1, vnclisten=0.0.0.0 ,vncunused=1']
instead of this:
vnc=1
vnclisten="0.0.0.0"
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v3: Split delay in non-essential (30 seconds) and essential
devices per Ian and Stefano suggestion]
[v4: Added comments per Stefano suggestion] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since we are using the m2p_override we do have struct pages
corresponding to the user vma mmap'ed by gntdev.
Removing the VM_PFNMAP flag makes get_user_pages work on that vma.
An example test case would be using a Xen userspace block backend
(QDISK) on a file on NFS using O_DIRECT.
Since 2.6.30-rc1 clps711x serial driver hungs system. This is a result
of call disable_irq from ISR. synchronize_irq waits for end of interrupt
and goes to infinite loop. This patch fix this problem.
Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[Patch not needed upstream as this is a backport build bugfix - gregkh
gcc correctly complains:
util/hist.c: In function ‘__hists__add_entry’:
util/hist.c:240:27: error: invalid type argument of ‘->’ (have ‘struct hist_entry’)
util/hist.c:241:23: error: invalid type argument of ‘->’ (have ‘struct hist_entry’)
for this new code:
+ if (he->ms.map != entry->ms.map) {
+ he->ms.map = entry->ms.map;
+ if (he->ms.map)
+ he->ms.map->referenced = true;
+ }
because "entry" is a "struct hist_entry", not a pointer to a struct.
In mainline, "entry" is a pointer to struct passed as argument to the function.
So this is broken during backporting. But obviously not compile tested.
Signed-off-by: Zeev Tarantov <zeev.tarantov@gmail.com> Cc: Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Git commit 36409f6353fc2d7b6516e631415f938eadd92ffa "use generic RCU
page-table freeing code" introduced a tlb flushing bug. Partially revert
the above git commit and go back to s390 specific page table flush code.
For s390 the TLB can contain three types of entries, "normal" TLB
page-table entries, TLB combined region-and-segment-table (CRST) entries
and real-space entries. Linux does not use real-space entries which
leaves normal TLB entries and CRST entries. The CRST entries are
intermediate steps in the page-table translation called translation paths.
For example a 4K page access in a three-level page table setup will
create two CRST TLB entries and one page-table TLB entry. The advantage
of that approach is that a page access next to the previous one can reuse
the CRST entries and needs just a single read from memory to create the
page-table TLB entry. The disadvantage is that the TLB flushing rules are
more complicated, before any page-table may be freed the TLB needs to be
flushed.
In short: the generic RCU page-table freeing code is incorrect for the
CRST entries, in particular the check for mm_users < 2 is troublesome.
This is applicable to 3.0+ kernels.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the force changes went in back in 3.3.0, we ended up returning
disconnected in the !force case, and the connected in when forced,
as it hit the hardcoded check.
Fix it so all exits go via the hardcoded check and stop spurious
modesets on platforms with hardcoded EDIDs.
Reported-by: Evan McNabb (Red Hat) Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The check of the encoder type in the commit [e00e8b5e: drm/radeon/kms:
fix analog load detection on DVI-I connectors] is obviously wrong, and
it's the culprit of the regression on my workstation with DVI-analog
connection resulting in the blank output.
Fixed the typo now.
Signed-off-by: Takashi Iwai <tiwai@suse.de> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It was possible to extract the robust list head address from a setuid
process if it had used set_robust_list(), allowing an ASLR info leak. This
changes the permission checks to be the same as those used for similar
info that comes out of /proc.
Running a setuid program that uses robust futexes would have had:
cred->euid != pcred->euid
cred->euid == pcred->uid
so the old permissions check would allow it. I'm not aware of any setuid
programs that use robust futexes, so this is just a preventative measure.
(This patch is based on changes from grsecurity.)
Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Darren Hart <dvhart@linux.intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: David Howells <dhowells@redhat.com> Cc: Serge E. Hallyn <serge.hallyn@canonical.com> Cc: kernel-hardening@lists.openwall.com Cc: spender@grsecurity.net Link: http://lkml.kernel.org/r/20120319231253.GA20893@www.outflux.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Eran <eran@over-here.org> Tested-by: Michal Labedzki <michal.labedzki@tieto.com> Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi> Cc: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a bitmap is added while the array is active, it is possible
for bitmap_daemon_work to run while the bitmap is being
initialised.
This is particularly a problem if bitmap_daemon_work sees
bitmap->filemap as non-NULL before it has been filled in properly.
So hold bitmap_info.mutex while filling in ->filemap
to prevent problems.
This patch is suitable for any -stable kernel, though it might not
apply cleanly before about 3.1.
Currently, Mode-Control register is accessed by read-modify-write.
According to DMA hardware specifications datasheet, prohibits this method.
Because this register resets to 0 by DMA HW after DMA transfer completes.
Thus, current read-modify-write processing can cause unexpected behavior.
The datasheet says in case of writing Mode-Control register, set the value for only target channel, the others must set '11b'.
e.g. Set DMA0=01b DMA11=10b
CTL0=33333331h
CTL2=00002333h
NOTE:
CTL0 includes DMA0~7 Mode-Control register.
CTL2 includes DMA8~11 Mode-Control register.
=================================
[ INFO: inconsistent lock state ]
2.6.39+ #89
---------------------------------
inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
rs232/822 [HC1[1]:SC0[0]:HE0:SE1] takes:
(&(&pd_chan->lock)->rlock){?.....}, at: [<c123b9a1>] pdc_desc_get+0x16/0xab
{HARDIRQ-ON-W} state was registered at:
[<c104fe28>] mark_irqflags+0xbd/0x11a
[<c1050386>] __lock_acquire+0x501/0x6bb
[<c1050945>] lock_acquire+0x63/0x7b
[<c131c51d>] _raw_spin_lock_bh+0x43/0x51
[<c123bee4>] pd_alloc_chan_resources+0x92/0x11e
[<c123ad62>] dma_chan_get+0x9b/0x107
[<c123b2d1>] __dma_request_channel+0x61/0xdc
[<c11ba24b>] pch_request_dma+0x61/0x19e
[<c11bb3b8>] pch_uart_startup+0x16a/0x1a2
[<c11b8446>] uart_startup+0x87/0x147
[<c11b9183>] uart_open+0x117/0x13e
[<c11a5c7d>] tty_open+0x23c/0x34c
[<c1097705>] chrdev_open+0x140/0x15f
[<c10930a6>] __dentry_open.clone.14+0x14a/0x22b
[<c1093dfb>] nameidata_to_filp+0x36/0x40
[<c109f28b>] do_last+0x513/0x635
[<c109f4af>] path_openat+0x9c/0x2aa
[<c109f6e4>] do_filp_open+0x27/0x69
[<c1093f02>] do_sys_open+0xfd/0x184
[<c1093fad>] sys_open+0x24/0x2a
[<c131d58c>] sysenter_do_call+0x12/0x32
irq event stamp: 2522
hardirqs last enabled at (2521): [<c131ca3b>] _raw_spin_unlock_irqrestore+0x36/0x52
hardirqs last disabled at (2522): [<c131db27>] common_interrupt+0x27/0x34
softirqs last enabled at (2354): [<c102fa11>] __do_softirq+0x10a/0x11a
softirqs last disabled at (2299): [<c10041a4>] do_softirq+0x57/0xa4
other info that might help us debug this:
2 locks held by rs232/822:
#0: (&tty->atomic_write_lock){+.+.+.}, at: [<c11a4b7a>] tty_write_lock+0x14/0x3c
#1: (&port_lock_key){-.....}, at: [<c11bad72>] pch_uart_interrupt+0x17/0x1e9
ISSUE: In case PCH_DMA with I2S communications with ch8~ch11, sometimes I2S data
is not send correctly.
CAUSE: The following patch I submitted before was not enough modification for
supporting DMA ch8~ch11. The modification for status register of ch8~11 was not
enough.
Currently, ".setup" function is not set.
As a result, when detecting our IOH's uart device without pch_uart, kernel panic
occurs at the following of pciserial_init_ports().
for (i = 0; i < nr_ports; i++) {
if (quirk->setup(priv, board, &serial_port, i))
break;
So, this patch adds the ".setup" function.
We can use pci_default_setup because our IOH's uart is compatible with 16550.
Add missing "personality.h"
security/commoncap.c: In function 'cap_bprm_set_creds':
security/commoncap.c:510: error: 'PER_CLEAR_ON_SETID' undeclared (first use in this function)
security/commoncap.c:510: error: (Each undeclared identifier is reported only once
security/commoncap.c:510: error: for each function it appears in.)
Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Cc: Eric Paris <eparis@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For above ASL code, we need to save scope node(\_SB) to lookup
the argument node(\_SB.RAMB).
Reported-by: Jim Green <student.northwestern@gmail.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ISSUE:
After a USB cable is connect/disconnected, the system rarely freezes.
CAUSE:
Since the USB device controller cannot know to disconnect the USB cable, when
it is used without detecting VBUS by GPIO, the UDC driver does not notify to
USB Gadget.
Since USB Gadget cannot know to disconnect, a false setting occurred when the
USB cable is connected/disconnect repeatedly.
ISSUE:
If the return value of pch_udc_pcd_init() is False, the return value of
this function is unsettled.
Since pch_udc_pcd_init() always returns 0, there is not actually the issue.
CAUSE:
If pch_udc_pcd_init() is True, the variable, retval, is not set for an
appropriate value.
Currently, external ROM access is enabled/disabled in probe()/remove().
So, when a buggy software access unanticipated memory area,
in case of enabling this ADE bit,
external ROM memory area can be broken.
This patch enables the ADE bit only accessing external ROM area.
Only ML7213/ML7223(Bus-n) has this register.
Currently,this driver doesn't care register "FUNCSEL" in suspend/resume.
This patch saves/restores FUNCSEL register only when the device is ML7213 or
ML7223(Bus-n).
Register "interrupt delay value" is for GbE which is connected to Bus-m of PCIe.
However currently, the value is set for Bus-n.
As a result, the value is not set correctly.
This patch moves setting the value processing of Bus-n to Bus-m.
Make sure hci_dev_open returns immediately if hci_dev_unregister has
been called.
This fixes a race between hci_dev_open and hci_dev_unregister which can
lead to a NULL-pointer dereference.
Bug is 100% reproducible using hciattach and a disconnected serial port:
0. # hciattach -n /dev/ttyO1 any noflow
1. hci_dev_open called from hci_power_on grabs req lock
2. hci_init_req executes but device fails to initialise (times out
eventually)
3. hci_dev_open is called from hci_sock_ioctl and sleeps on req lock
4. hci_uart_tty_close calls hci_dev_unregister and sleeps on req lock in
hci_dev_do_close
5. hci_dev_open (1) releases req lock
6. hci_dev_do_close grabs req lock and returns as device is not up
7. hci_dev_unregister sleeps in destroy_workqueue
8. hci_dev_open (3) grabs req lock, calls hci_init_req and eventually sleeps
9. hci_dev_unregister finishes, while hci_dev_open is still running...
The xHCI 1.0 spec errata released on June 13, 2011, changes the ordering
that the xHCI registers are saved and restored in. It moves the
interrupt pending (IMAN) and interrupt control (IMOD) registers to be
saved and restored last. I believe that's because the host controller
may attempt to fetch the event ring table when interrupts are
re-enabled. Therefore we need to restore the event ring registers
before we re-enable interrupts.
This should be backported to kernels as old as 2.6.37, that contain the
commit 5535b1d5f8885695c6ded783c692e3c0d0eda8ca "USB: xHCI: PCI power
management implementation"
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Tested-by: Elric Fu <elricfu1@gmail.com> Cc: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the maximum noise floor limit is set as too high (-60dB). The
assumption of having a higher threshold limit is that it would help
de-sensitize the receiver (reduce phy errors) from continuous
interference. But when we have a bursty interference where there are
collisions and then free air time and if the receiver is desensitized too
much, it will miss the normal packets too. Lets make use of chips
specific min, nom and max limits always. This patch helps to improve the
connection stability in congested networks.
Cc: Paul Stewart <pstew@google.com> Tested-by: Gary Morain <gmorain@google.com> Signed-off-by: Madhan Jaganathan <madhanj@qca.qualcomm.com> Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.0/3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a process increases permissions using fcaps all of the dangerous
personality flags which are cleared for suid apps should also be cleared.
Thus programs given priviledge with fcaps will continue to have address space
randomization enabled even if the parent tried to disable it to make it
easier to attack.
Signed-off-by: Eric Paris <eparis@redhat.com> Reviewed-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 360f748b204275229f8398cb2f9f53955db1503b
"serial: PL011: clear pending interrupts"
attempts to clear interrupts by writing to a
yet-unassigned memory address. This fixes the issue.
The breaking patch is marked for stable so should be
carried along with the other patch.
Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Nicolas Pitre <nico@fluxnic.net> Reported-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Chanho Min reported that when the boot loader transfers
control to the kernel, there may be pending interrupts
causing the UART to lock up in an eternal loop trying to
pick tokens from the FIFO (since the RX interrupt flag
indicates there are tokens) while in practice there are
no tokens - in fact there is only a pending IRQ flag.
This patch address the issue with a combination of two
patches suggested by Russell King that clears and mask
all interrupts at probe() and clears any pending error
and RX interrupts at port startup time.
We suspect the spurious interrupts are a side-effect of
switching the UART from FIFO to non-FIFO mode.
Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com> Reported-by: Chanho Min <chanho0207@gmail.com> Suggested-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Jong-Sung Kim <neidhard.kim@lge.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The suspend operation of VIA xHCI host have some issues and
hibernate operation works fine, so The XHCI_RESET_ON_RESUME
quirk is added for it.
This patch should base on "xHCI: Don't write zeroed pointer
to xHC registers" that is released by Sarah. Otherwise, the
host system error will ocurr in the hibernate operation
process.
This should be backported to stable kernels as old as 2.6.37,
that contain the commit c877b3b2ad5cb9d4fe523c5496185cc328ff3ae9
"xhci: Add reset on resume quirk for asrock p67 host".
Signed-off-by: Elric Fu <elricfu1@gmail.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Re-define XHCI_LEGACY_DISABLE_SMI and used it in right way. All SMI enable
bits will be cleared to zero and flag bits 29:31 are also cleared to zero.
Other bits should be presvered as Table 146.
This patch should be backported to kernels as old as 2.6.31.
Signed-off-by: Alex He <alex.he@amd.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The xhci_save_registers() function saved the event ring dequeue pointer
in the s3 register structure, but xhci_restore_registers() never
restored it. No other code in the xHCI successful resume path would
ever restore it either. Fix that.
This should be backported to kernels as old as 2.6.37, that contain the
commit 5535b1d5f8885695c6ded783c692e3c0d0eda8ca "USB: xHCI: PCI power
management implementation".
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Tested-by: Elric Fu <elricfu1@gmail.com> Cc: Andiry Xu <andiry.xu@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When xhci_mem_cleanup() is called, we can't be sure if the xHC is
actually halted. We can ask the xHC to halt by writing to the RUN bit
in the command register, but that might timeout due to a HW hang.
If the host controller is still running, we should not write zeroed
values to the event ring dequeue pointers or base tables, the DCBAA
pointers, or the command ring pointers. Eric Fu reports his VIA VL800
host accesses the event ring pointers after a failed register restore on
resume from suspend. The hypothesis is that the host never actually
halted before the register write to change the event ring pointer to
zero.
Remove all writes of zeroed values to pointer registers in
xhci_mem_cleanup(). Instead, make all callers of the function reset the
host controller first, which will reset those registers to zero.
xhci_mem_init() is the only caller that doesn't first halt and reset the
host controller before calling xhci_mem_cleanup().
This should be backported to kernels as old as 2.6.32.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Tested-by: Elric Fu <elricfu1@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While we're at that, define IMAN bitfield to aid readability.
The interrupt enable bit should be set once on driver init, and we
shouldn't need to continually re-enable it. Commit c21599a3 introduced
a read of the irq_pending register, and that allows us to preserve the
state of the IE bit. Before that commit, we were blindly writing 0x3 to
the register.
This patch should be backported to kernels as old as 2.6.36, or ones
that contain the commit c21599a36165dbc78b380846b254017a548b9de5 "USB:
xhci: Reduce reads and writes of interrupter registers".
Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1517b) fixes an error in the USB scatter-gather library.
The library code uses urb->dev to determine whether or nor an URB is
currently active; the completion handler sets urb->dev to NULL.
However the core unlinking routines need to use urb->dev. Since
unlinking always racing with completion, the completion handler must
not clear urb->dev -- it can lead to invalid memory accesses when a
transfer has to be cancelled.
This patch fixes the problem by getting rid of the lines that clear
urb->dev after urb has been submitted. As a result we may end up
trying to unlink an URB that failed in submission or that has already
completed, so an extra check is added after each unlink to avoid
printing an error message when this happens. The checks are updated
in both sg_complete() and sg_cancel(), and the second is updated to
match the first (currently it prints out unnecessary warning messages
if a device is unplugged while a transfer is in progress).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-and-tested-by: Illia Zaitsev <I.Zaitsev@adbglobal.com> CC: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix race between probe and open by making sure that the disconnected
flag is not cleared until all ports have been registered.
A call to tty_open while probe is running may get a reference to the
serial structure in serial_install before its ports have been
registered. This may lead to usb_serial_core calling driver open before
port is fully initialised.
With ftdi_sio this result in the following NULL-pointer dereference as
the private data has not been initialised at open:
Fix tick_nohz_restart() to not use a stale ktime_t "now" value when
calling tick_do_update_jiffies64(now).
If we reach this point in the loop it means that we crossed a tick
boundary since we grabbed the "now" timestamp, so at this point "now"
refers to a time in the old jiffy, so using the old value for "now" is
incorrect, and is likely to give us a stale jiffies value.
In particular, the first time through the loop the
tick_do_update_jiffies64(now) call is always a no-op, since the
caller, tick_nohz_restart_sched_tick(), will have already called
tick_do_update_jiffies64(now) with that "now" value.
Note that tick_nohz_stop_sched_tick() already uses the correct
approach: when we notice we cross a jiffy boundary, grab a new
timestamp with ktime_get(), and *then* update jiffies.
When a process exec()'s, all the maps are retired, but we keep the hist
entries around which hold references to those outdated maps.
If the same library gets mapped in for which we have hist entries, a new
map will be created. But when we take a perf entry hit within that map,
we'll find the existing hist entry with the older map.
This causes symbol translations to be done incorrectly. For example,
the perf entry processing will lookup the correct uptodate map entry and
use that to calculate the symbol and DSO relative address. But later
when we update the histogram we'll translate the address using the
outdated map file instead leading to conditions such as out-of-range
offsets in symbol__inc_addr_samples().
Therefore, update the map of the hist_entry dynamically at lookup/
creation time.
The total number of scatter gather elements in the CISS command
used by the scsi tape code was being cast to a u8, which can hold
at most 255 scatter gather elements. It should have been cast to
a u16. Without this patch the command gets rejected by the controller
since the total scatter gather count did not add up to the right
value resulting in an i/o error.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The default is too small (1024 blocks), use h->cciss_max_sectors (8192 blocks)
Without this change, if you try to set the block size of a tape drive above
512*1024, via "mt -f /dev/st0 setblk nnn" where nnn is greater than 524288,
it won't work right.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The DS driver registers as a subsys_initcall() but this can be too
early, in particular this risks registering before we've had a chance
to allocate and setup module_kset in kernel/params.c which is
performed also as a subsyts_initcall().
Register DS using device_initcall() insteal.
Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The invocation of softirq is now handled by irq_exit(), so there is no
need for sparc64 to invoke it on the trap-return path. In fact, doing so
is a bug because if the trap occurred in the idle loop, this invocation
can result in lockdep-RCU failures. The problem is that RCU ignores idle
CPUs, and the sparc64 trap-return path to the softirq handlers fails to
tell RCU that the CPU must be considered non-idle while those handlers
are executing. This means that RCU is ignoring any RCU read-side critical
sections in those handlers, which in turn means that RCU-protected data
can be yanked out from under those read-side critical sections.
The shiny new lockdep-RCU ability to detect RCU read-side critical sections
that RCU is ignoring located this problem.
The fix is straightforward: Make sparc64 stop manually invoking the
softirq handlers.
Reported-by: Meelis Roos <mroos@linux.ee> Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Client data was assigned to iio_dev structure in probe but in
hmc5843_init_client function casted to private driver data structure which
is wrong. Possibly calling mutex_init(&data->lock); corrupt data
which the lead to above crash.
Signed-off-by: Marek Belisko <marek.belisko@open-nandra.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suppose a multi-threaded task forks a new process (on cpu A), thus
bumping up the ref count on all the pages. While the fork is occurring
(and thus we have marked all the PTEs as read-only), another thread in
the original process (on cpu B) tries to write to a huge page, taking an
access violation from the write-protect and calling hugetlb_cow(). Now,
suppose the fork() fails. It will undo the COW and decrement the ref
count on the pages, so the ref count on the huge page drops back to 1.
Meanwhile hugetlb_cow() also decrements the ref count by one on the
original page, since the original address space doesn't need it any
more, having copied a new page to replace the original page. This
leaves the ref count at zero, and when we call unlock_page(), we panic.
fork on CPU A fault on CPU B
============= ==============
...
down_write(&parent->mmap_sem);
down_write_nested(&child->mmap_sem);
...
while duplicating vmas
if error
break;
...
up_write(&child->mmap_sem);
up_write(&parent->mmap_sem); ...
down_read(&parent->mmap_sem);
...
lock_page(page);
handle COW
page_mapcount(old_page) == 2
alloc and prepare new_page
...
handle error
page_remove_rmap(page);
put_page(page);
...
fold new_page into pte
page_remove_rmap(page);
put_page(page);
...
oops ==> unlock_page(page);
up_read(&parent->mmap_sem);
The solution is to take an extra reference to the page while we are
holding the lock on it.
The ST variants of the PL031 all require bit 26 in the control register
to be set before they work properly. Discovered this when testing on
the Nomadik board where it would suprisingly just stand still.
Michel Lespinasse cleaned up the futex calling conventions in commit 37a9d912b24f ("futex: Sanitize cmpxchg_futex_value_locked API").
But the ia64 implementation was subtly broken. Gcc does not know that
register "r8" will be updated by the fault handler if the cmpxchg
instruction takes an exception. So it feels safe in letting the
initialization of r8 slide to after the cmpxchg. Result: we always
return 0 whether the user address faulted or not.
Fix by moving the initialization of r8 into the __asm__ code so gcc
won't move it.
Do not close protocol driver until device has been unregistered.
This fixes a race between tty_close and hci_dev_open which can result in
a NULL-pointer dereference.
The line discipline closes the protocol driver while we may still have
hci_dev_open sleeping on the req_lock mutex resulting in a NULL-pointer
dereference when lock is acquired and hci_init_req called.
Bug is 100% reproducible using hciattach and a disconnected serial port:
0. # hciattach -n ttyO1 any noflow
1. hci_dev_open called from hci_power_on grabs req lock
2. hci_init_req executes but device fails to initialise (times out
eventually)
3. hci_dev_open is called from hci_sock_ioctl and sleeps on req lock
4. hci_uart_tty_close detaches protocol driver and cancels init req
5. hci_dev_open (1) releases req lock
6. hci_dev_open (3) grabs req lock, calls hci_init_req, which triggers oops
when request is prepared in hci_uart_send_frame
Bluetooth: uart-ldisc: Fix memory leak and remove destruct cb
We currently leak the hci_uart object if HCI_UART_PROTO_SET is never set
because the hci-destruct callback will then never be called. This fix
removes the hci-destruct callback and frees the driver internal private
hci_uart object directly on tty-close. We call hci_unregister_dev() here
so the hci-core will never call our callbacks again (except destruct).
Therefore, we can safely free the driver internal data right away and
set the destruct callback to NULL.
Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently when ThumbEE is not enabled (!CONFIG_ARM_THUMBEE) the ThumbEE
register states are not saved/restored at context switch. The default state
of the ThumbEE Ctrl register (TEECR) allows userspace accesses to the
ThumbEE Base Handler register (TEEHBR). This can cause unexpected behaviour
when people use ThumbEE on !CONFIG_ARM_THUMBEE kernels, as well as allowing
covert communication - eg between userspace tasks running inside chroot
jails.
This patch sets up TEECR in order to prevent user-space access to TEEHBR
when !CONFIG_ARM_THUMBEE. In this case, tasks are sent SIGILL if they try to
access TEEHBR.
Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Jonathan Austin <jonathan.austin@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In https://bugzilla.kernel.org/show_bug.cgi?id=42976, a system with driver
rtl8192se used as an AP suffers from "Out of SW-IOMMU space" errors. These
are caused by the DMA buffers used for beacons never being unmapped.
This bug was also reported at
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/961618
Reported-and-Tested-by: Da Xue <da@lessconfused.com> Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It seems it can corrupt the monitor EDID in certain cases on certain
boards when running sensors detect. It's rarely used anyway outside
of AIW boards.
The 845g shares the errata with i830 whereby executing a command
within 2 cachelines of the end of the ringbuffer may cause a GPU hang.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 330605423c fixed l2cap conn establishment for non-ssp remote
devices by not setting HCI_CONN_ENCRYPT_PEND every time conn security
is tested (which was always returning failure on any subsequent
security checks).
However, this broke l2cap conn establishment for ssp remote devices
when an ACL link was already established at SDP-level security. This
fix ensures that encryption must be pending whenever authentication
is also pending.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Tested-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Userspace can pass in arbitrary combinations of MS_* flags to mount().
If both MS_BIND and one of MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE are
passed, device name which should be checked for MS_BIND was not checked because
MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE had higher priority than MS_BIND.
If both one of MS_BIND/MS_MOVE and MS_REMOUNT are passed, device name which
should not be checked for MS_REMOUNT was checked because MS_BIND/MS_MOVE had
higher priority than MS_REMOUNT.
Fix these bugs by changing priority to MS_REMOUNT -> MS_BIND ->
MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE -> MS_MOVE as with do_mount() does.
Also, unconditionally return -EINVAL if more than one of
MS_SHARED/MS_PRIVATE/MS_SLAVE/MS_UNBINDABLE is passed so that TOMOYO will not
generate inaccurate audit logs, for commit 7a2e8a8f "VFS: Sanity check mount
flags passed to change_mnt_propagation()" clarified that these flags must be
exclusively passed.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Unfortunatly the interrupts for the event log and the
peripheral page-faults are only enabled at boot but not
re-enabled at resume. Fix that.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
[bwh: Backport to 3.0:
- Drop change to PPR log which was added in 3.3
- Source is under arch/x86/kernel] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
keyctl_session_to_parent(task) sets ->replacement_session_keyring,
it should be processed and cleared by key_replace_session_keyring().
However, this task can fork before it notices TIF_NOTIFY_RESUME and
the new child gets the bogus ->replacement_session_keyring copied by
dup_task_struct(). This is obviously wrong and, if nothing else, this
leads to put_cred(already_freed_cred).
change copy_creds() to clear this member. If copy_process() fails
before this point the wrong ->replacement_session_keyring doesn't
matter, exit_creds() won't be called.
Added Vendor/Device Id of Motorola Rokr E6 (22b8:6027) so it can be
recognized by the "zaurus" USBNet driver.
Applies to Linux 3.2.13 and 2.6.39.4. Signed-off-by: Guan Xin <guanx.bac@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
TWL6030 family of PMIC use a shadow interrupt status register
while kernel processes the current interrupt event.
However, any write(0 or 1) to register INT_STS_A, INT_STS_B or
INT_STS_C clears all 3 interrupt status registers.
Since clear of the interrupt is done on 32k clk, depending on I2C
bus speed, we could in-adverently clear the status of a interrupt
status pending on shadow register in the current implementation.
This is due to the fact that multi-byte i2c write operation into
three seperate status register could result in multiple load
and clear of status and result in lost interrupts.
Instead, doing a single byte write to INT_STS_A register with 0x0
will clear all three interrupt status registers without the related
risk.
When a machine boots up, the TSC generally gets reset. However,
when kexec is used to boot into a kernel, the TSC value would be
carried over from the previous kernel. The computation of
cycns_offset in set_cyc2ns_scale is prone to an overflow, if the
machine has been up more than 208 days prior to the kexec. The
overflow happens when we multiply *scale, even though there is
enough room to store the final answer.
We fix this issue by decomposing tsc_now into the quotient and
remainder of division by CYC2NS_SCALE_FACTOR and then performing
the multiplication separately on the two components.
Refactor code to share the calculation with the previous
fix in __cycles_2_ns().
Signed-off-by: Salman Qazi <sqazi@google.com> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Turner <pjt@google.com> Cc: john stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/20120310004027.19291.88460.stgit@dungbeetle.mtv.corp.google.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Mike Galbraith <efault@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
WARNING: at drivers/pci/pci.c:118 pci_ioremap_bar+0x24/0x52()
when probing his sound card, and sound did not work. After adding
pci=use_crs to the kernel command line, no more trouble.
Ok, we can add a quirk. dmidecode output reveals that this is an MSI
MS-7253, for which we already have a quirk, but the short-sighted
author tied the quirk to a single BIOS version, making it not kick in
on Carlos's machine with BIOS V1.2. If a later BIOS update makes it
no longer necessary to look at the _CRS info it will still be
harmless, so let's stop trying to guess which versions have and don't
have accurate _CRS tables.
Addresses https://bugtrack.alsa-project.org/alsa-bug/view.php?id=5533
Also see <https://bugzilla.kernel.org/show_bug.cgi?id=42619>.
Reported-by: Carlos Luna <caralu74@gmail.com> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the spirit of commit 29cf7a30f8a0 ("x86/PCI: use host bridge _CRS
info on ASUS M2V-MX SE"), this DMI quirk turns on "pci_use_crs" by
default on a board that needs it.
This fixes boot failures and oopses introduced in 3e3da00c01d0
("x86/pci: AMD one chain system to use pci read out res"). The quirk
is quite targetted (to a specific board and BIOS version) for two
reasons:
(1) to emphasize that this method of tackling the problem one quirk
at a time is a little insane
(2) to give BIOS vendors an opportunity to use simpler tables and
allow us to return to generic behavior (whatever that happens to
be) with a later BIOS update
In other words, I am not at all happy with having quirks like this.
But it is even worse for the kernel not to work out of the box on
these machines, so...
Commit f02e8a6596b7 ("module: Sort exported symbols") sorts symbols
placing each of them in its own elf section. This sorting and merging
into the canonical sections are done by the linker.
Unfortunately modpost to generate Module.symvers file parses vmlinux.o
(which is not linked yet) and all modules object files (which aren't
linked yet). These aren't sanitized by the linker yet. That breaks
modpost that can't detect license properly for modules.
This patch makes modpost aware of the new exported symbols structure.
[ This above is a slightly corrected version of the explanation of the
problem, copied from commit 62a2635610db ("modpost: Fix modpost's
license checking V3"). That commit fixed the problem for module
object files, but not for vmlinux.o. This patch fixes modpost for
vmlinux.o. ]
Signed-off-by: Frank Rowand <frank.rowand@am.sony.com> Signed-off-by: Alessio Igor Bogani <abogani@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit f02e8a6 sorts symbols placing each of them in its own elf section.
The sorting and merging into the canonical sections are done by the linker.
Unfortunately modpost to generate Module.symvers file parses vmlinux
(already linked) and all modules object files (which aren't linked yet).
These aren't sanitized by the linker yet. That breaks modpost that can't
detect license properly for modules. This patch makes modpost aware of
the new exported symbols structure.
Thanks to Arnaud Lacombe <lacombar@gmail.com> and Anders Kaseorg
<andersk@ksplice.com> for providing useful suggestions about code.
This work was supported by a hardware donation from the CE Linux Forum.
Reported-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Alessio Igor Bogani <abogani@kernel.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit bfdc0b4 adds code to restrict access to dmesg_restrict,
however, it incorrectly alters kptr_restrict rather than
dmesg_restrict.
The original patch from Richard Weinberger
(https://lkml.org/lkml/2011/3/14/362) alters dmesg_restrict as
expected, and so the patch seems to have been misapplied.
This adds the CAP_SYS_ADMIN check to both dmesg_restrict and
kptr_restrict, since both are sensitive.
There has long been a limitation using software breakpoints with a
kernel compiled with CONFIG_DEBUG_RODATA going back to 2.6.26. For
this particular patch, it will apply cleanly and has been tested all
the way back to 2.6.36.
The kprobes code uses the text_poke() function which accommodates
writing a breakpoint into a read-only page. The x86 kgdb code can
solve the problem similarly by overriding the default breakpoint
set/remove routines and using text_poke() directly.
The x86 kgdb code will first attempt to use the traditional
probe_kernel_write(), and next try using a the text_poke() function.
The break point install method is tracked such that the correct break
point removal routine will get called later on.
Cc: x86@kernel.org Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Inspried-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The do_fork and sys_open tests have never worked properly on anything
other than a UP configuration with the kgdb test suite. This is
because the test suite did not fully implement the behavior of a real
debugger. A real debugger tracks the state of what thread it asked to
single step and can correctly continue other threads of execution or
conditionally stop while waiting for the original thread single step
request to return.
Below is a simple method to cause a fatal kernel oops with the kgdb
test suite on a 2 processor ARM system:
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
echo V1I1F100 > /sys/module/kgdbts/parameters/kgdbts
Very soon after starting the test the kernel will start warning with
messages like:
kgdbts: BP mismatch c002487c expected c0024878
------------[ cut here ]------------
WARNING: at drivers/misc/kgdbts.c:317 check_and_rewind_pc+0x9c/0xc4()
[<c01f6520>] (check_and_rewind_pc+0x9c/0xc4)
[<c01f595c>] (validate_simple_test+0x3c/0xc4)
[<c01f60d4>] (run_simple_test+0x1e8/0x274)
The kernel will eventually recovers, but the test suite has completely
failed to test anything useful.
This patch implements behavior similar to a real debugger that does
not rely on hardware single stepping by using only software planted
breakpoints.
In order to mimic a real debugger, the kgdb test suite now tracks the
most recent thread that was continued (cont_thread_id), with the
intent to single step just this thread. When the response to the
single step request stops in a different thread that hit the original
break point that thread will now get continued, while the debugger
waits for the thread with the single step pending. Here is a high
level description of the sequence of events.
cont_instead_of_sstep = 0;
1) set breakpoint at do_fork
2) continue
3) Save the thread id where we stop to cont_thread_id
4) Remove breakpoint at do_fork
5) Reset the PC if needed depending on kernel exception type
6) soft single step
7) Check where we stopped
if current thread != cont_thread_id {
if (here for more than 2 times for the same thead) {
### must be a really busy system, start test again ###
goto step 1
}
goto step 5
} else {
cont_instead_of_sstep = 0;
}
8) clean up and run test again if needed
9) Clear out any threads that were waiting on a break point at the
point in time the test is ended with get_cont_catch(). This
happens sometimes because breakpoints are used in place of single
stepping and some threads could have been in the debugger exception
handling queue because breakpoints were hit concurrently on
different CPUs. This also means we wait at least one second before
unplumbing the debugger connection at the very end, so as respond
to any debug threads waiting to be serviced.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The do_fork and sys_open tests have never worked properly on anything
other than a UP configuration with the kgdb test suite. This is
because the test suite did not fully implement the behavior of a real
debugger. A real debugger tracks the state of what thread it asked to
single step and can correctly continue other threads of execution or
conditionally stop while waiting for the original thread single step
request to return.
Below is a simple method to cause a fatal kernel oops with the kgdb
test suite on a 4 processor x86 system:
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
while [ 1 ] ; do ls > /dev/null 2> /dev/null; done&
echo V1I1F1000 > /sys/module/kgdbts/parameters/kgdbts
Very soon after starting the test the kernel will oops with a message like:
The warn will turn to a hard kernel crash shortly after that because
the pc will not get properly rewound to the right value after hitting
a breakpoint leading to a hard lockup.
This change is broken up into 2 pieces because archs that have hw
single stepping (2.6.26 and up) need different changes than archs that
do not have hw single stepping (3.0 and up). This change implements
the correct behavior for an arch that supports hw single stepping.
A minor defect was fixed where sys_open should be do_sys_open
for the sys_open break point test. This solves the problem of running
a 64 bit with a 32 bit user space. The sys_open() never gets called
when using the 32 bit file system for the kgdb testsuite because the
32 bit binaries invoke the compat_sys_open() call leading to the test
never completing.
In order to mimic a real debugger, the kgdb test suite now tracks the
most recent thread that was continued (cont_thread_id), with the
intent to single step just this thread. When the response to the
single step request stops in a different thread that hit the original
break point that thread will now get continued, while the debugger
waits for the thread with the single step pending. Here is a high
level description of the sequence of events.
cont_instead_of_sstep = 0;
1) set breakpoint at do_fork
2) continue
3) Save the thread id where we stop to cont_thread_id
4) Remove breakpoint at do_fork
5) Reset the PC if needed depending on kernel exception type
6) if (cont_instead_of_sstep) { continue } else { single step }
7) Check where we stopped
if current thread != cont_thread_id {
cont_instead_of_sstep = 1;
goto step 5
} else {
cont_instead_of_sstep = 0;
}
8) clean up and run test again if needed
Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / karo-tx-linux.git / log