Enabled when the device supports KEEP FCS and IGNORE FCS.
When the flag is set, pass all received frames up the stack,
even ones with invalid FCS, controlled by ethtool.
Signed-off-by: Muhammad Mahajna <muhammadm@mellanox.com>
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Enabled when device supports KEEP FCS. When the flag is set, Ethernet FCS
is appended to the end of the frame, controlled by ethtool.
Signed-off-by: Muhammad Mahajna <muhammadm@mellanox.com>
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for the interface ethtool identify feature.
Make the physical port LED to blink with green and yellow colors.
The device handles the LED blink by itself (synchrous use of
set_phys_id), by returning 0 to ETHTOOL_ID_ACTIVE command.
Signed-off-by: Eyal Grossman <eyalgr@mellanox.com>
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The calls to SET_PORT used hard-code numbers, when supplying command's
opcode modifiers, fix that to use well defined constants.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If HCA supports ETS QoS feature, set enhanced QoS bit in init_hca as default.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A new capability bit was introduced in the past to to differ devices
using the QoS ETS feature. The old was deprecated since then.
If driver sees device which set only the old capabilty, it will print
warning to user suggesting to upgrade the FW.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Support granular QoS per VF, by implementing the ndo_set_vf_rate.
Enforce a rate limit per VF when called, and enabled only for VFs in
VST mode with user priority supported by the device.
We don't enforce VFs to be in VST mode at the moment of configuration,
but rather save the given rate limit and enforce it when the VF is
moved to VST with user priority which is supported (currently 0).
VST<->VGT or VST qos value state changes are disallowed when a rate
limit is configured. Minimum BW share is not supported yet.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Granular QoS per VF feature introduce a new QP field, qos_vport.
PF administrator can connect VF QPs to a certain QoS Vport, to
inherit its proporties. Connecting QPs to the default QoS Vport
(defined as 0) is always allowed, even when there are no allocated VPPs.
At this point, only the default vport is connected to QPs.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initialization of granular Qos per VF mechanism.
Query the port availible VPPs and allocates those on all supported
priorities in an equal share. Allocation is done only in SRIOV mode,
when the feature is supported by the device and port type is Ethernet.
Allocation currently is done only on the default priority 0.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Checks in QUERY_DEV_CAP if the granular QoS per VF feature is
supported by the device. Disabled for guests.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the SET_VPORT_QOS device command, which is ntended for virtual
granular QoS configuration per VF in SRIOV mode. The SET_VPORT_QOS
command sets and queries QoS parameters of a VPort. Each priority
allowed for a VPort is assigned with a share of the BW, and a BW
limitation. QoS parameters can be modified at any time, but must be
initialized before any QP is associated with the VPort.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implements device ALLOCATE_VPP command, to be used for granular QoS
configuration of VFs by the PF device. Defines and queries the amount
of VPPs assigned to each port, and the amount of VPPs assigned to each
priority of each port. Once the total VPPs are split between the priorities
of a port, they may be assigned with a share of the BW or a rate limit.
Split into two functions (get/set) whoch are supplied with
mlx4_alloc_vpp_context and physical port number.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Create two new files fw_qos.h and fw_qos.c in mlx4_core module.
It gathers all relevant QoS firmware related commands etc, thus improving
encapsulation of the mlx4_core module. For now it contains the QoS existing
commands: mlx4_SET_PORT_SCHEDULER and mlx4_SET_PORT_PRIO2TC.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previous vf_oper and vf_admin code created very long lines, making it hard
to read the code. Added relevant in-struct pointers to reduce code
complexity and avoid code lines spread over 80 lines. Same logic is preserved.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently implemented as static function in resource_tracker.c --
this change will allow other files in mlx4_core to use it as well.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently any change of netdev features results in a call to
mlx4_en_update_loopback_state(). Those calls are unnecessary,
and should be called only upon loopback feature change.
Also moved some of the logic into mlx4_en_update_loopback_state().
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Enable RSS support for fragmented IP packets, when device supports it.
Until now, fragmented IP packets were directed only to the default_qpn.
Since IP fragments (datagram) have no upper protocols (L3 IP packets),
hash is performed on 3-tuple - dst MAC, source IP and dest IP. The HW
makes sure that this holds for the 1st fragment too, so all fragments
go to the same QP.
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
xen-netfront limits transmitted skbs to be at most 44 segments in size. However,
GSO permits up to 65536 bytes, which means a maximum of 45 segments of 1448
bytes each. This slight reduction in the size of packets means a slight loss in
efficiency.
Since c/s 9ecd1a75d, xen-netfront sets gso_max_size to
XEN_NETIF_MAX_TX_SIZE - MAX_TCP_HEADER,
where XEN_NETIF_MAX_TX_SIZE is 65535 bytes.
The calculation used by tcp_tso_autosize (and also tcp_xmit_size_goal since c/s
6c09fa09d) in determining when to split an skb into two is
sk->sk_gso_max_size - 1 - MAX_TCP_HEADER.
So the maximum permitted size of an skb is calculated to be
(XEN_NETIF_MAX_TX_SIZE - MAX_TCP_HEADER) - 1 - MAX_TCP_HEADER.
Intuitively, this looks like the wrong formula -- we don't need two TCP headers.
Instead, there is no need to deviate from the default gso_max_size of 65536 as
this already accommodates the size of the header.
Currently, the largest skb transmitted by netfront is 63712 bytes (44 segments
of 1448 bytes each), as observed via tcpdump. This patch makes netfront send
skbs of up to 65160 bytes (45 segments of 1448 bytes each).
Similarly, the maximum allowable mtu does not need to subtract MAX_TCP_HEADER as
it relates to the size of the whole packet, including the header.
Fixes: 9ecd1a75d9 ("xen-netfront: reduce gso_max_size to account for max TCP header")
Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/usb/asix_common.c
drivers/net/usb/sr9800.c
drivers/net/usb/usbnet.c
include/linux/usb/usbnet.h
net/ipv4/tcp_ipv4.c
net/ipv6/tcp_ipv6.c
The TCP conflicts were overlapping changes. In 'net' we added a
READ_ONCE() to the socket cached RX route read, whilst in 'net-next'
Eric Dumazet touched the surrounding code dealing with how mini
sockets are handled.
With USB, it's a case of the same bug fix first going into net-next
and then I cherry picked it back into net.
Signed-off-by: David S. Miller <davem@davemloft.net>
When the LE pivacy feature is used, then pairing has to happen based
on resolvable random addresses (RPA), but currently there is no clean
way to retrieve the correct RPA. So instead of returning an outdated
RPA, just disallow this command when LE privacy is in use.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Pull dmaengine fixes from Vinod Koul:
"This time we have addition of caps for jz4740 which fixes intentional
warning at boot. Then we have memory leak issues in drivers using
virt-dma by Peter on few drive"
* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: moxart-dma: Fix memory leak when stopping a running transfer
dmaengine: bcm2835-dma: Fix memory leak when stopping a running transfer
dmaengine: omap-dma: Fix memory leak when terminating running transfer
dmaengine: edma: fix memory leak when terminating running transfers
dmaengine: jz4740: Define capabilities
Pull networking fixes from David Miller:
1) Fix use-after-free with mac80211 RX A-MPDU reorder timer, from
Johannes Berg.
2) iwlwifi leaks memory every module load/unload cycles, fix from Larry
Finger.
3) Need to use for_each_netdev_safe() in rtnl_group_changelink()
otherwise we can crash, from WANG Cong.
4) mlx4 driver does register_netdev() too early in the probe sequence,
from Ido Shamay.
5) Don't allow router discovery hop limit to decrease the interface's
hop limit, from D.S. Ljungmark.
6) tx_packets and tx_bytes improperly accounted for certain classes of
USB network devices, fix from Ben Hutchings.
7) ip{6}mr_rules_init() mistakenly use plain kfree to release the ipmr
tables in the error path, they must instead use ip{6}mr_free_table().
Fix from WANG Cong.
8) cxgb4 doesn't properly quiesce all RX activity before unregistering
the netdevice. Fix from Hariprasad Shenai.
9) Fix hash corruptions in ipvlan driver, from Jiri Benc.
10) nla_memcpy(), like a real memcpy, should fully initialize the
destination buffer, even if the source attribute is smaller. Fix
from Jiri Benc.
11) Fix wrong error code returned from iucv_sock_sendmsg(). We should
use whatever sock_alloc_send_skb() put into 'err'. From Eugene
Crosser.
12) Fix slab object leak on module unload in TIPC, from Ying Xue.
13) Need a READ_ONCE() when reading the cached RX socket route in
tcp_v{4,6}_early_demux(). From Michal Kubecek.
14) Still too many problems with TPC support in the ath9k driver, so
disable it for now. From Felix Fietkau.
15) When in AP mode the rtlwifi driver can leak DMA mappings, fix from
Larry Finger.
16) Missing kzalloc() failure check in gs_usb CAN driver, from Colin Ian
King.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (52 commits)
cxgb4: Fix to dump devlog, even if FW is crashed
cxgb4: Firmware macro changes for fw verison 1.13.32.0
bnx2x: Fix kdump when iommu=on
bnx2x: Fix kdump on 4-port device
mac80211: fix RX A-MPDU session reorder timer deletion
MAINTAINERS: Update Intel Wired Ethernet Driver info
tipc: fix a slab object leak
net/usb/r8152: add device id for Lenovo TP USB 3.0 Ethernet
af_iucv: fix AF_IUCV sendmsg() errno
openvswitch: Return vport module ref before destruction
netlink: pad nla_memcpy dest buffer with zeroes
bonding: Bonding Overriding Configuration logic restored.
ipvlan: fix check for IP addresses in control path
ipvlan: do not use rcu operations for address list
ipvlan: protect against concurrent link removal
ipvlan: fix addr hash list corruption
net: fec: setup right value for mdio hold time
net: tcp6: fix double call of tcp_v6_fill_cb()
cxgb4vf: Fix sparse warnings
netns: don't clear nsid too early on removal
...
Nicolas Dichtel says:
====================
Remove iflink field from the net_device structure
The first goal of this series was to advertise the veth peer via the IFLA_LINK
attribute, but iflink was not ready for network namespaces.
The iflink of an interface should be set to its ifindex for a physical interface
and to another value (0 if not relevant) for a virtual interface.
This was not the case for some interfaces, like vxlan, bond, or bridge for
example.
There is also a risk, if the targeted interface moves to another netns, that the
ifindex changes without updating corresponding iflink fields (eg. vlan).
Moving the management of this property into virtual interface drivers allows to
better handle this last case because most of virtual interface drivers have a
pointer to the link netdevice.
Anyway, dev->iflink value was always a copy of some internal data of the virtual
interface driver, thus let's use these internal data directly.
So, this series removes the iflink field and let the drivers manage it.
Only the last patch was present in the v1, but I fully rework it.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that the peer netns is advertised in rtnl messages, we can set this property
so that IFLA_LINK will advertise the peer ifindex. It allows the userland to get
the full veth configuration.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Virtual interfaces are supposed to set an iflink value != of their ifindex.
It was not the case for some of them, like vxlan, bond or bridge.
Let's set iflink to 0 when dev->rtnl_link_ops is set.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that all users of iflink have the ndo_get_iflink handler available, it's
possible to remove this field.
By default, dev_get_iflink() returns the ifindex of the interface.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't use dev->iflink anymore.
CC: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't use dev->iflink anymore.
CC: Roland Dreier <roland@kernel.org>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't use dev->iflink anymore.
CC: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't use dev->iflink anymore.
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't use dev->iflink anymore.
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't use dev->iflink anymore.
CC: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't use dev->iflink anymore.
CC: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The goal of this patch is to prepare the removal of the iflink field. It
introduces a new ndo function, which will be implemented by virtual interfaces.
There is no functional change into this patch. All readers of iflink field
now call dev_get_iflink().
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Properly verify that the resulting page aligned end address is larger
than both the start address and the length of the memory area requested.
Both the start and length arguments for ib_umem_get are controlled by
the user. A misbehaving user can provide values which will cause an
integer overflow when calculating the page aligned end address.
This overflow can cause also miscalculation of the number of pages
mapped, and additional logic issues.
Addresses: CVE-2014-8159
Cc: <stable@vger.kernel.org>
Signed-off-by: Shachar Raindel <raindel@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Some of the CYCLE_ACTIVITY.* events can only be scheduled on
counter 2. Due to a typo Haswell matched those with
INTEL_EVENT_CONSTRAINT, which lead to the events never
matching as the comparison does not expect anything
in the umask too. Fix the typo.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1425925222-32361-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For supporting Intel LBR branches filtering, Intel LBR sharing logic
mechanism is introduced from commit b36817e886 ("perf/x86: Add Intel
LBR sharing logic"). It modifies __intel_shared_reg_get_constraints() to
config lbr_sel, which is finally used to set LBR_SELECT.
However, the intel_shared_regs_constraints() function is called after
intel_pebs_constraints(). The PEBS event will return immediately after
intel_pebs_constraints(). So it's impossible to filter branches for PEBS
events.
This patch moves intel_shared_regs_constraints() ahead of
intel_pebs_constraints().
We can safely do that because the intel_shared_regs_constraints() function
only returns empty constraint if its rejecting the event, otherwise it
returns NULL such that we continue calling intel_pebs_constraints() and
x86_get_event_constraint().
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1427467105-9260-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that there's a HCI request API available where the callback receives
the resulting skb, we can convert the local OOB data reading to use this
new API. This patch does the necessary update in mgmt.c (which also
requires moving the callback higher up since it's now a static function)
and removes the custom calls from hci_event.c that are no-longer
necessary.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To make the hci_req_run_skb() API consistent with hci_cmd_sync_ev()
the callback should receive the cmd_complete parameters in the 'normal'
case and the full HCI event if a special event was expected. This patch
moves the hci_get_cmd_complete() function from hci_core.c to hci_event.c
where it's used to strip the skb from the needed headers before passing
it on to the callback.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The hci_req_pending() function has no users anymore, so simply remove
it.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that the synchronous HCI requests use the new API and a new private
variable the recv_evt member of hci_dev is no-longer needed. This patch
removes it.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Now that there's an API in place that allows passing the resulting skb
to the request callback we can conveniently convert the hci_req_sync and
related functions to use it. Since we still need to get the skb from the
async callback into the sleeping _sync() function the patch adds another
req_skb variable to hci_dev where the sync request state is tracked.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds a second possible callback for HCI requests where the
callback will receive the full skb of the last successfully completed
HCI command. This API is useful for cases where we want to use a request
to read some data and the existing hci_event.c handlers do not store it
e.g. in the hci_dev struct.
The reason the patch is a bit bigger than just adding the new API is
because the hci_req_cmd_complete() functions required some refactoring
to enable it: now hci_req_cmd_complete() is simply used to request the
callback pointers if any, and the actual calling of them happens from a
single place at the end of hci_event_packet(). The reason for this is
that we need to pass the original skb (without any skb_pull, etc
modifications done to it) and it's simplest to keep track of it within
the hci_event_packet() function.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When dealing with HCI command status events, the reasoning for trying to
mark a request as complete if no specific event is being waited for and
status was success is not self-evident. This patch adds a clarifying
comment above the if-statement.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We need to wait for all fences, not just the exclusive one.
Signed-off-by: Christian König <christian.koenig@amd.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
We somehow try to free the SG table twice.
Bugs: https://bugs.freedesktop.org/show_bug.cgi?id=89734
Signed-off-by: Christian König <christian.koenig@amd.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
When performing a modeset, use the framebuffer pitch value to set FIMD
IMG_SIZE and Mixer SPAN registers. These are both defined as pitch - the
distance between contiguous lines (bytes for FIMD, pixels for mixer).
Fixes display on Snow (1366x768).
Signed-off-by: Daniel Stone <daniels@collabora.com>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
This patch fixes an error in kgdb for x86_64 which would report
the value of dx when asked to give the value of si.
Signed-off-by: Steffen Liebergeld <steffen.liebergeld@kernkonzept.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When I wrote the opportunistic SYSRET code, I missed an important difference
between SYSRET and IRET.
Both instructions are capable of setting EFLAGS.TF, but they behave differently
when doing so:
- IRET will not issue a #DB trap after execution when it sets TF.
This is critical -- otherwise you'd never be able to make forward progress when
returning to userspace.
- SYSRET, on the other hand, will trap with #DB immediately after
returning to CPL3, and the next instruction will never execute.
This breaks anything that opportunistically SYSRETs to a user
context with TF set. For example, running this code with TF set
and a SIGTRAP handler loaded never gets past 'post_nop':
extern unsigned char post_nop[];
asm volatile ("pushfq\n\t"
"popq %%r11\n\t"
"nop\n\t"
"post_nop:"
: : "c" (post_nop) : "r11");
In my defense, I can't find this documented in the AMD or Intel manual.
Fix it by using IRET to restore TF.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 2a23c6b8a9 ("x86_64, entry: Use sysret to return to userspace when possible")
Link: http://lkml.kernel.org/r/9472f1ca4c19a38ecda45bba9c91b7168135fcfa.1427923514.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Muhammad Mahajna