1. 06 6月, 2018 1 次提交
    • U
      PM / Domains: Add support for multi PM domains per device to genpd · 3c095f32
      Ulf Hansson 提交于
      To support devices being partitioned across multiple PM domains, let's
      begin with extending genpd to cope with these kind of configurations.
      
      Therefore, add a new exported function genpd_dev_pm_attach_by_id(), which
      is similar to the existing genpd_dev_pm_attach(), but with the difference
      that it allows its callers to provide an index to the PM domain that it
      wants to attach.
      
      Note that, genpd_dev_pm_attach_by_id() shall only be called by the driver
      core / PM core, similar to how the existing dev_pm_domain_attach() makes
      use of genpd_dev_pm_attach(). However, this is implemented by following
      changes on top.
      
      Because, only one PM domain can be attached per device, genpd needs to
      create a virtual device that it can attach/detach instead. More precisely,
      let the new function genpd_dev_pm_attach_by_id() register a virtual struct
      device via calling device_register(). Then let it attach this device to the
      corresponding PM domain, rather than the one that is provided by the
      caller. The actual attaching is done via re-using the existing genpd OF
      functions.
      
      At successful attachment, genpd_dev_pm_attach_by_id() returns the created
      virtual device, which allows the caller to operate on it to deal with power
      management. Following changes on top, provides more details in this
      regards.
      
      To deal with detaching of a PM domain for the multiple PM domains case,
      let's also extend the existing genpd_dev_pm_detach() function, to cover the
      cleanup of the created virtual device, via make it call device_unregister()
      on it. In this way, there is no need to introduce a new function to deal
      with detach for the multiple PM domain case, but instead the existing one
      is re-used.
      Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
      Acked-by: NJon Hunter <jonathanh@nvidia.com>
      Tested-by: NJon Hunter <jonathanh@nvidia.com>
      Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
      Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      3c095f32
  2. 05 6月, 2018 1 次提交
    • L
      swait: strengthen language to discourage use · c5e7a7ea
      Linus Torvalds 提交于
      We already earlier discouraged people from using this interface in
      commit 88796e7e ("sched/swait: Document it clearly that the swait
      facilities are special and shouldn't be used"), but I just got a pull
      request with a new broken user.
      
      So make the comment *really* clear.
      
      The swait interfaces are bad, and should not be used unless you have
      some *very* strong reasons that include tons of hard performance numbers
      on just why you want to use them, and you show that you actually
      understand that they aren't at all like the normal wait/wakeup
      interfaces.
      
      So far, every single user has been suspect.  The main user is KVM, which
      is completely pointless (there is only ever one waiter, which avoids the
      interface subtleties, but also means that having a queue instead of a
      pointer is counter-productive and certainly not an "optimization").
      
      So make the comments much stronger.
      
      Not that anybody likely reads them anyway, but there's always some
      slight hope that it will cause somebody to think twice.
      
      I'd like to remove this interface entirely, but there is the theoretical
      possibility that it's actually the right thing to use in some situation,
      most likely some deep RT use.
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c5e7a7ea
  3. 03 6月, 2018 1 次提交
    • J
      block: don't use blocking queue entered for recursive bio submits · cd4a4ae4
      Jens Axboe 提交于
      If we end up splitting a bio and the queue goes away between
      the initial submission and the later split submission, then we
      can block forever in blk_queue_enter() waiting for the reference
      to drop to zero. This will never happen, since we already hold
      a reference.
      
      Mark a split bio as already having entered the queue, so we can
      just use the live non-blocking queue enter variant.
      
      Thanks to Tetsuo Handa for the analysis.
      
      Reported-by: syzbot+c4f9cebf9d651f6e54de@syzkaller.appspotmail.com
      Signed-off-by: NJens Axboe <axboe@kernel.dk>
      cd4a4ae4
  4. 02 6月, 2018 1 次提交
    • D
      bpf: fix uapi hole for 32 bit compat applications · 36f9814a
      Daniel Borkmann 提交于
      In 64 bit, we have a 4 byte hole between ifindex and netns_dev in the
      case of struct bpf_map_info but also struct bpf_prog_info. In net-next
      commit b85fab0e ("bpf: Add gpl_compatible flag to struct bpf_prog_info")
      added a bitfield into it to expose some flags related to programs. Thus,
      add an unnamed __u32 bitfield for both so that alignment keeps the same
      in both 32 and 64 bit cases, and can be naturally extended from there
      as in b85fab0e.
      
      Before:
      
        # file test.o
        test.o: ELF 32-bit LSB relocatable, Intel 80386, version 1 (SYSV), not stripped
        # pahole test.o
        struct bpf_map_info {
      	__u32                      type;                 /*     0     4 */
      	__u32                      id;                   /*     4     4 */
      	__u32                      key_size;             /*     8     4 */
      	__u32                      value_size;           /*    12     4 */
      	__u32                      max_entries;          /*    16     4 */
      	__u32                      map_flags;            /*    20     4 */
      	char                       name[16];             /*    24    16 */
      	__u32                      ifindex;              /*    40     4 */
      	__u64                      netns_dev;            /*    44     8 */
      	__u64                      netns_ino;            /*    52     8 */
      
      	/* size: 64, cachelines: 1, members: 10 */
      	/* padding: 4 */
        };
      
      After (same as on 64 bit):
      
        # file test.o
        test.o: ELF 32-bit LSB relocatable, Intel 80386, version 1 (SYSV), not stripped
        # pahole test.o
        struct bpf_map_info {
      	__u32                      type;                 /*     0     4 */
      	__u32                      id;                   /*     4     4 */
      	__u32                      key_size;             /*     8     4 */
      	__u32                      value_size;           /*    12     4 */
      	__u32                      max_entries;          /*    16     4 */
      	__u32                      map_flags;            /*    20     4 */
      	char                       name[16];             /*    24    16 */
      	__u32                      ifindex;              /*    40     4 */
      
      	/* XXX 4 bytes hole, try to pack */
      
      	__u64                      netns_dev;            /*    48     8 */
      	__u64                      netns_ino;            /*    56     8 */
      	/* --- cacheline 1 boundary (64 bytes) --- */
      
      	/* size: 64, cachelines: 1, members: 10 */
      	/* sum members: 60, holes: 1, sum holes: 4 */
        };
      Reported-by: NDmitry V. Levin <ldv@altlinux.org>
      Reported-by: NEugene Syromiatnikov <esyr@redhat.com>
      Fixes: 52775b33 ("bpf: offload: report device information about offloaded maps")
      Fixes: 675fc275 ("bpf: offload: report device information for offloaded programs")
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      36f9814a
  5. 01 6月, 2018 5 次提交
  6. 31 5月, 2018 10 次提交
  7. 30 5月, 2018 5 次提交
  8. 29 5月, 2018 16 次提交
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