This patch is to add reconf chunk event based on the sctp event
frame in rx path, it will call sctp_sf_do_reconf to process the
reconf chunk.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to add a function to process the incoming reconf chunk,
in which it verifies the chunk, and traverses the param and process
it with the right function one by one.
sctp_sf_do_reconf would be the process function of reconf chunk event.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to add a function sctp_verify_reconf to do some length
check and multi-params check for sctp stream reconf according to rfc6525
section 3.1.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to implement Receiver-Side Procedures for the Incoming
SSN Reset Request Parameter described in rfc6525 section 5.2.3.
It's also to move str_list endian conversion out of sctp_make_strreset_req,
so that sctp_make_strreset_req can be used more conveniently to process
inreq.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to implement Receiver-Side Procedures for the Outgoing
SSN Reset Request Parameter described in rfc6525 section 5.2.2.
Note that some checks must be after request_seq check, as even those
checks fail, strreset_inseq still has to be increase by 1.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to add Stream Reset Event described in rfc6525
section 6.1.1.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to define Re-configuration Response Parameter described
in rfc6525 section 4.4. As optional fields are only for SSN/TSN Reset
Request Parameter, it uses another function to make that.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On the kernel side, sockaddr_storage is #define'd to
__kernel_sockaddr_storage. Replacing struct sockaddr_storage with
struct __kernel_sockaddr_storage defined by <linux/socket.h> fixes
the following linux/rds.h userspace compilation error:
/usr/include/linux/rds.h:226:26: error: field 'dest_addr' has incomplete type
struct sockaddr_storage dest_addr;
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Consistently use types from linux/types.h to fix the following
linux/rds.h userspace compilation errors:
/usr/include/linux/rds.h:106:2: error: unknown type name 'uint8_t'
uint8_t name[32];
/usr/include/linux/rds.h:107:2: error: unknown type name 'uint64_t'
uint64_t value;
/usr/include/linux/rds.h:117:2: error: unknown type name 'uint64_t'
uint64_t next_tx_seq;
/usr/include/linux/rds.h:118:2: error: unknown type name 'uint64_t'
uint64_t next_rx_seq;
/usr/include/linux/rds.h:121:2: error: unknown type name 'uint8_t'
uint8_t transport[TRANSNAMSIZ]; /* null term ascii */
/usr/include/linux/rds.h:122:2: error: unknown type name 'uint8_t'
uint8_t flags;
/usr/include/linux/rds.h:129:2: error: unknown type name 'uint64_t'
uint64_t seq;
/usr/include/linux/rds.h:130:2: error: unknown type name 'uint32_t'
uint32_t len;
/usr/include/linux/rds.h:135:2: error: unknown type name 'uint8_t'
uint8_t flags;
/usr/include/linux/rds.h:139:2: error: unknown type name 'uint32_t'
uint32_t sndbuf;
/usr/include/linux/rds.h:144:2: error: unknown type name 'uint32_t'
uint32_t rcvbuf;
/usr/include/linux/rds.h:145:2: error: unknown type name 'uint64_t'
uint64_t inum;
/usr/include/linux/rds.h:153:2: error: unknown type name 'uint64_t'
uint64_t hdr_rem;
/usr/include/linux/rds.h:154:2: error: unknown type name 'uint64_t'
uint64_t data_rem;
/usr/include/linux/rds.h:155:2: error: unknown type name 'uint32_t'
uint32_t last_sent_nxt;
/usr/include/linux/rds.h:156:2: error: unknown type name 'uint32_t'
uint32_t last_expected_una;
/usr/include/linux/rds.h:157:2: error: unknown type name 'uint32_t'
uint32_t last_seen_una;
/usr/include/linux/rds.h:164:2: error: unknown type name 'uint8_t'
uint8_t src_gid[RDS_IB_GID_LEN];
/usr/include/linux/rds.h:165:2: error: unknown type name 'uint8_t'
uint8_t dst_gid[RDS_IB_GID_LEN];
/usr/include/linux/rds.h:167:2: error: unknown type name 'uint32_t'
uint32_t max_send_wr;
/usr/include/linux/rds.h:168:2: error: unknown type name 'uint32_t'
uint32_t max_recv_wr;
/usr/include/linux/rds.h:169:2: error: unknown type name 'uint32_t'
uint32_t max_send_sge;
/usr/include/linux/rds.h:170:2: error: unknown type name 'uint32_t'
uint32_t rdma_mr_max;
/usr/include/linux/rds.h:171:2: error: unknown type name 'uint32_t'
uint32_t rdma_mr_size;
/usr/include/linux/rds.h:212:9: error: unknown type name 'uint64_t'
typedef uint64_t rds_rdma_cookie_t;
/usr/include/linux/rds.h:215:2: error: unknown type name 'uint64_t'
uint64_t addr;
/usr/include/linux/rds.h:216:2: error: unknown type name 'uint64_t'
uint64_t bytes;
/usr/include/linux/rds.h:221:2: error: unknown type name 'uint64_t'
uint64_t cookie_addr;
/usr/include/linux/rds.h:222:2: error: unknown type name 'uint64_t'
uint64_t flags;
/usr/include/linux/rds.h:228:2: error: unknown type name 'uint64_t'
uint64_t cookie_addr;
/usr/include/linux/rds.h:229:2: error: unknown type name 'uint64_t'
uint64_t flags;
/usr/include/linux/rds.h:234:2: error: unknown type name 'uint64_t'
uint64_t flags;
/usr/include/linux/rds.h:240:2: error: unknown type name 'uint64_t'
uint64_t local_vec_addr;
/usr/include/linux/rds.h:241:2: error: unknown type name 'uint64_t'
uint64_t nr_local;
/usr/include/linux/rds.h:242:2: error: unknown type name 'uint64_t'
uint64_t flags;
/usr/include/linux/rds.h:243:2: error: unknown type name 'uint64_t'
uint64_t user_token;
/usr/include/linux/rds.h:248:2: error: unknown type name 'uint64_t'
uint64_t local_addr;
/usr/include/linux/rds.h:249:2: error: unknown type name 'uint64_t'
uint64_t remote_addr;
/usr/include/linux/rds.h:252:4: error: unknown type name 'uint64_t'
uint64_t compare;
/usr/include/linux/rds.h:253:4: error: unknown type name 'uint64_t'
uint64_t swap;
/usr/include/linux/rds.h:256:4: error: unknown type name 'uint64_t'
uint64_t add;
/usr/include/linux/rds.h:259:4: error: unknown type name 'uint64_t'
uint64_t compare;
/usr/include/linux/rds.h:260:4: error: unknown type name 'uint64_t'
uint64_t swap;
/usr/include/linux/rds.h:261:4: error: unknown type name 'uint64_t'
uint64_t compare_mask;
/usr/include/linux/rds.h:262:4: error: unknown type name 'uint64_t'
uint64_t swap_mask;
/usr/include/linux/rds.h:265:4: error: unknown type name 'uint64_t'
uint64_t add;
/usr/include/linux/rds.h:266:4: error: unknown type name 'uint64_t'
uint64_t nocarry_mask;
/usr/include/linux/rds.h:269:2: error: unknown type name 'uint64_t'
uint64_t flags;
/usr/include/linux/rds.h:270:2: error: unknown type name 'uint64_t'
uint64_t user_token;
/usr/include/linux/rds.h:274:2: error: unknown type name 'uint64_t'
uint64_t user_token;
/usr/include/linux/rds.h:275:2: error: unknown type name 'int32_t'
int32_t status;
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Include <linux/in.h> to fix the following linux/mroute.h userspace
compilation errors:
/usr/include/linux/mroute.h:58:18: error: field 'vifc_lcl_addr' has incomplete type
struct in_addr vifc_lcl_addr; /* Local interface address */
/usr/include/linux/mroute.h:61:17: error: field 'vifc_rmt_addr' has incomplete type
struct in_addr vifc_rmt_addr; /* IPIP tunnel addr */
/usr/include/linux/mroute.h:72:17: error: field 'mfcc_origin' has incomplete type
struct in_addr mfcc_origin; /* Origin of mcast */
/usr/include/linux/mroute.h:73:17: error: field 'mfcc_mcastgrp' has incomplete type
struct in_addr mfcc_mcastgrp; /* Group in question */
/usr/include/linux/mroute.h:84:17: error: field 'src' has incomplete type
struct in_addr src;
/usr/include/linux/mroute.h:85:17: error: field 'grp' has incomplete type
struct in_addr grp;
/usr/include/linux/mroute.h:109:17: error: field 'im_src' has incomplete type
struct in_addr im_src,im_dst;
/usr/include/linux/mroute.h:109:24: error: field 'im_dst' has incomplete type
struct in_addr im_src,im_dst;
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Include <linux/in6.h> to fix the following linux/mroute6.h userspace
compilation errors:
/usr/include/linux/mroute6.h:80:22: error: field 'mf6cc_origin' has incomplete type
struct sockaddr_in6 mf6cc_origin; /* Origin of mcast */
/usr/include/linux/mroute6.h:81:22: error: field 'mf6cc_mcastgrp' has incomplete type
struct sockaddr_in6 mf6cc_mcastgrp; /* Group in question */
/usr/include/linux/mroute6.h:91:22: error: field 'src' has incomplete type
struct sockaddr_in6 src;
/usr/include/linux/mroute6.h:92:22: error: field 'grp' has incomplete type
struct sockaddr_in6 grp;
/usr/include/linux/mroute6.h:132:18: error: field 'im6_src' has incomplete type
struct in6_addr im6_src, im6_dst;
/usr/include/linux/mroute6.h:132:27: error: field 'im6_dst' has incomplete type
struct in6_addr im6_src, im6_dst;
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Include <linux/in6.h> to fix the following linux/ipv6_route.h userspace
compilation errors:
/usr/include/linux/ipv6_route.h:42:19: error: field 'rtmsg_dst' has incomplete type
struct in6_addr rtmsg_dst;
/usr/include/linux/ipv6_route.h:43:19: error: field 'rtmsg_src' has incomplete type
struct in6_addr rtmsg_src;
/ust/include/linux/ipv6_route.h:44:19: error: field 'rtmsg_gateway' has incomplete type
struct in6_addr rtmsg_gateway;
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds the backbone required for the various HW initalizations
which are necessary for the FCoE driver (qedf) for QLogic FastLinQ
4xxxx line of adapters - FW notification, resource initializations, etc.
Signed-off-by: Arun Easi <arun.easi@cavium.com>
Signed-off-by: Yuval Mintz <yuval.mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The send complete for RC QPs mismanages the ack count when the
responder side is only in RTR.
A QP in that state cannot send requests, but it can be the target
for operations that elicit responses.
Adjust the RC completion logic to correct the count maintenance
by reflecting RECV_OK in a new state test.
Reviewed-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Convert copy_sge and related SGE state functions to use boolean.
For determining if QP is in user mode, add helper function in rdmavt_qp.h.
This is used to determine if QP needs the last byte ordering.
While here, change rvt_pd.user to a boolean.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Having per-CPU reference count for each MR prevents
cache-line bouncing across the system. Thus, it
prevents bottlenecks. Use per-CPU reference counts
per MR.
The per-CPU reference count for FMRs is used in
atomic mode to allow accurate testing of the busy
state. Other MR types run in per-CPU mode MR until
they're freed.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Consistently use types from linux/types.h to fix the following
linux/target_core_user.h userspace compilation errors:
/usr/include/linux/target_core_user.h:108:4: error: unknown type name 'uint32_t'
uint32_t iov_cnt;
/usr/include/linux/target_core_user.h:109:4: error: unknown type name 'uint32_t'
uint32_t iov_bidi_cnt;
/usr/include/linux/target_core_user.h:110:4: error: unknown type name 'uint32_t'
uint32_t iov_dif_cnt;
/usr/include/linux/target_core_user.h:111:4: error: unknown type name 'uint64_t'
uint64_t cdb_off;
/usr/include/linux/target_core_user.h:112:4: error: unknown type name 'uint64_t'
uint64_t __pad1;
/usr/include/linux/target_core_user.h:113:4: error: unknown type name 'uint64_t'
uint64_t __pad2;
/usr/include/linux/target_core_user.h:117:4: error: unknown type name 'uint8_t'
uint8_t scsi_status;
/usr/include/linux/target_core_user.h:118:4: error: unknown type name 'uint8_t'
uint8_t __pad1;
/usr/include/linux/target_core_user.h:119:4: error: unknown type name 'uint16_t'
uint16_t __pad2;
/usr/include/linux/target_core_user.h:120:4: error: unknown type name 'uint32_t'
uint32_t __pad3;
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Split iscsit_check_dataout_hdr() into two functions
1. __iscsit_check_dataout_hdr() - This function
validates data out hdr.
2. iscsit_check_dataout_hdr() - This function finds
iSCSI cmd using iscsit_find_cmd_from_itt_or_dump(),
then it calls __iscsit_check_dataout_hdr() to
validate iSCSI hdr.
This split is required to support Chelsio T6 iSCSI
DDP completion feature. T6 adapters reduce number of
completions to host by generating single completion
for all directly placed(DDP) iSCSI pdus in a sequence,
DDP completion contains iSCSI hdr of the last pdu in a
sequence.
On receiving DDP completion cxgbit driver will first
find iSCSI cmd using iscsit_find_cmd_from_itt_or_dump()
then updates cmd->write_data_done, cmd->next_burst_len,
cmd->data_sn and calls __iscsit_check_dataout_hdr()
to validate iSCSI hdr.
(Move XRDSL check ahead of itt lookup / dump - nab)
Signed-off-by: Varun Prakash <varun@chelsio.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Add driver to support the Multi-Inno MI0283QT display panel.
It has an ILI9341 MIPI DBI compatible display controller.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Add support for MIPI DBI compatible controllers.
Interface type C option 1 and 3 are supported (SPI).
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Thierry Reding <treding@nvidia.com>
tinydrm provides helpers for very simple displays that can use
CMA backed framebuffers and need flushing on changes.
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Thierry Reding <treding@nvidia.com>
We need to verify that the controller supports the security
commands before actually trying to issue them.
Signed-off-by: Scott Bauer <scott.bauer@intel.com>
[hch: moved the check so that we don't call into the OPAL code if not
supported]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Insted of bloating the containing structure with it all the time this
allocates struct opal_dev dynamically. Additionally this allows moving
the definition of struct opal_dev into sed-opal.c. For this a new
private data field is added to it that is passed to the send/receive
callback. After that a lot of internals can be made private as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Scott Bauer <scott.bauer@intel.com>
Reviewed-by: Scott Bauer <scott.bauer@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Long standing issue with JITed programs is that stack traces from
function tracing check whether a given address is kernel code
through {__,}kernel_text_address(), which checks for code in core
kernel, modules and dynamically allocated ftrace trampolines. But
what is still missing is BPF JITed programs (interpreted programs
are not an issue as __bpf_prog_run() will be attributed to them),
thus when a stack trace is triggered, the code walking the stack
won't see any of the JITed ones. The same for address correlation
done from user space via reading /proc/kallsyms. This is read by
tools like perf, but the latter is also useful for permanent live
tracing with eBPF itself in combination with stack maps when other
eBPF types are part of the callchain. See offwaketime example on
dumping stack from a map.
This work tries to tackle that issue by making the addresses and
symbols known to the kernel. The lookup from *kernel_text_address()
is implemented through a latched RB tree that can be read under
RCU in fast-path that is also shared for symbol/size/offset lookup
for a specific given address in kallsyms. The slow-path iteration
through all symbols in the seq file done via RCU list, which holds
a tiny fraction of all exported ksyms, usually below 0.1 percent.
Function symbols are exported as bpf_prog_<tag>, in order to aide
debugging and attribution. This facility is currently enabled for
root-only when bpf_jit_kallsyms is set to 1, and disabled if hardening
is active in any mode. The rationale behind this is that still a lot
of systems ship with world read permissions on kallsyms thus addresses
should not get suddenly exposed for them. If that situation gets
much better in future, we always have the option to change the
default on this. Likewise, unprivileged programs are not allowed
to add entries there either, but that is less of a concern as most
such programs types relevant in this context are for root-only anyway.
If enabled, call graphs and stack traces will then show a correct
attribution; one example is illustrated below, where the trace is
now visible in tooling such as perf script --kallsyms=/proc/kallsyms
and friends.
Before:
7fff8166889d bpf_clone_redirect+0x80007f0020ed (/lib/modules/4.9.0-rc8+/build/vmlinux)
f5d80 __sendmsg_nocancel+0xffff006451f1a007 (/usr/lib64/libc-2.18.so)
After:
7fff816688b7 bpf_clone_redirect+0x80007f002107 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fffa0575728 bpf_prog_33c45a467c9e061a+0x8000600020fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fffa07ef1fc cls_bpf_classify+0x8000600020dc (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff81678b68 tc_classify+0x80007f002078 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164d40b __netif_receive_skb_core+0x80007f0025fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164d718 __netif_receive_skb+0x80007f002018 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164e565 process_backlog+0x80007f002095 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164dc71 net_rx_action+0x80007f002231 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff81767461 __softirqentry_text_start+0x80007f0020d1 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff817658ac do_softirq_own_stack+0x80007f00201c (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff810a2c20 do_softirq+0x80007f002050 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff810a2cb5 __local_bh_enable_ip+0x80007f002085 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8168d452 ip_finish_output2+0x80007f002152 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8168ea3d ip_finish_output+0x80007f00217d (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8168f2af ip_output+0x80007f00203f (/lib/modules/4.9.0-rc8+/build/vmlinux)
[...]
7fff81005854 do_syscall_64+0x80007f002054 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff817649eb return_from_SYSCALL_64+0x80007f002000 (/lib/modules/4.9.0-rc8+/build/vmlinux)
f5d80 __sendmsg_nocancel+0xffff01c484812007 (/usr/lib64/libc-2.18.so)
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the dummy bpf_jit_compile() stubs for eBPF JITs and make
that a single __weak function in the core that can be overridden
similarly to the eBPF one. Also remove stale pr_err() mentions
of bpf_jit_compile.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds code that handles GFP_ATOMIC kmalloc failure on
insertion. As we cannot use vmalloc, we solve it by making our
hash table nested. That is, we allocate single pages at each level
and reach our desired table size by nesting them.
When a nested table is created, only a single page is allocated
at the top-level. Lower levels are allocated on demand during
insertion. Therefore for each insertion to succeed, only two
(non-consecutive) pages are needed.
After a nested table is created, a rehash will be scheduled in
order to switch to a vmalloced table as soon as possible. Also,
the rehash code will never rehash into a nested table. If we
detect a nested table during a rehash, the rehash will be aborted
and a new rehash will be scheduled.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently there is no way of querying whether a filter is
offloaded to HW or not when using "both" policy (where none
of skip_sw or skip_hw flags are set by user-space).
Add two new flags, "in hw" and "not in hw" such that user
space can determine if a filter is actually offloaded to
hw or not. The "in hw" UAPI semantics was chosen so it's
similar to the "skip hw" flag logic.
If none of these two flags are set, this signals running
over older kernel.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Amir Vadai <amir@vadai.me>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The purpose of the KVM_SET_SIGNAL_MASK API is to let userspace "kick"
a VCPU out of KVM_RUN through a POSIX signal. A signal is attached
to a dummy signal handler; by blocking the signal outside KVM_RUN and
unblocking it inside, this possible race is closed:
VCPU thread service thread
--------------------------------------------------------------
check flag
set flag
raise signal
(signal handler does nothing)
KVM_RUN
However, one issue with KVM_SET_SIGNAL_MASK is that it has to take
tsk->sighand->siglock on every KVM_RUN. This lock is often on a
remote NUMA node, because it is on the node of a thread's creator.
Taking this lock can be very expensive if there are many userspace
exits (as is the case for SMP Windows VMs without Hyper-V reference
time counter).
As an alternative, we can put the flag directly in kvm_run so that
KVM can see it:
VCPU thread service thread
--------------------------------------------------------------
raise signal
signal handler
set run->immediate_exit
KVM_RUN
check run->immediate_exit
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>