1. 19 Aug, 2015 3 commits
    • James Hogan's avatar
      MIPS: do_mcheck: Fix kernel code dump with EVA · e5e8829b
      James Hogan authored
      [ Upstream commit 55c723e1 ]
      
      If a machine check exception is raised in kernel mode, user context,
      with EVA enabled, then the do_mcheck handler will attempt to read the
      code around the EPC using EVA load instructions, i.e. as if the reads
      were from user mode. This will either read random user data if the
      process has anything mapped at the same address, or it will cause an
      exception which is handled by __get_user, resulting in this output:
      
       Code: (Bad address in epc)
      
      Fix by setting the current user access mode to kernel if the saved
      register context indicates the exception was taken in kernel mode. This
      causes __get_user to use normal loads to read the kernel code.
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Cc: Markos Chandras <markos.chandras@imgtec.com>
      Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
      Cc: linux-mips@linux-mips.org
      Cc: <stable@vger.kernel.org> # 3.15+
      Patchwork: https://patchwork.linux-mips.org/patch/10777/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      e5e8829b
    • Felix Fietkau's avatar
      MIPS: Fix sched_getaffinity with MT FPAFF enabled · be98cdc0
      Felix Fietkau authored
      [ Upstream commit 1d62d737 ]
      
      p->thread.user_cpus_allowed is zero-initialized and is only filled on
      the first sched_setaffinity call.
      
      To avoid adding overhead in the task initialization codepath, simply OR
      the returned mask in sched_getaffinity with p->cpus_allowed.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarFelix Fietkau <nbd@openwrt.org>
      Cc: linux-mips@linux-mips.org
      Patchwork: https://patchwork.linux-mips.org/patch/10740/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      be98cdc0
    • James Hogan's avatar
      MIPS: Malta: Don't reinitialise RTC · edf9af78
      James Hogan authored
      [ Upstream commit 106eccb4 ]
      
      On Malta, since commit a87ea88d ("MIPS: Malta: initialise the RTC at
      boot"), the RTC is reinitialised and forced into binary coded decimal
      (BCD) mode during init, even if the bootloader has already initialised
      it, and may even have already put it into binary mode (as YAMON does).
      This corrupts the current time, can result in the RTC seconds being an
      invalid BCD (e.g. 0x1a..0x1f) for up to 6 seconds, as well as confusing
      YAMON for a while after reset, enough for it to report timeouts when
      attempting to load from TFTP (it actually uses the RTC in that code).
      
      Therefore only initialise the RTC to the extent that is necessary so
      that Linux avoids interfering with the bootloader setup, while also
      allowing it to estimate the CPU frequency without hanging, without a
      bootloader necessarily having done anything with the RTC (for example
      when the kernel is loaded via EJTAG).
      
      The divider control is configured for a 32KHZ reference clock if
      necessary, and the SET bit of the RTC_CONTROL register is cleared if
      necessary without changing any other bits (this bit will be set when
      coming out of reset if the battery has been disconnected).
      
      Fixes: a87ea88d ("MIPS: Malta: initialise the RTC at boot")
      Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
      Reviewed-by: default avatarPaul Burton <paul.burton@imgtec.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Maciej W. Rozycki <macro@linux-mips.org>
      Cc: linux-mips@linux-mips.org
      Cc: <stable@vger.kernel.org> # 3.14+
      Patchwork: https://patchwork.linux-mips.org/patch/10739/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      edf9af78
  2. 07 Aug, 2015 1 commit
  3. 06 Aug, 2015 2 commits
    • Ming Lei's avatar
      blk-mq: fix CPU hotplug handling · df0e5109
      Ming Lei authored
      [ Upstream commit 2a34c087 ]
      
      hctx->tags has to be set as NULL in case that it is to be unmapped
      no matter if set->tags[hctx->queue_num] is NULL or not in blk_mq_map_swqueue()
      because shared tags can be freed already from another request queue.
      
      The same situation has to be considered during handling CPU online too.
      Unmapped hw queue can be remapped after CPU topo is changed, so we need
      to allocate tags for the hw queue in blk_mq_map_swqueue(). Then tags
      allocation for hw queue can be removed in hctx cpu online notifier, and it
      is reasonable to do that after mapping is updated.
      
      Cc: <stable@vger.kernel.org>
      Reported-by: default avatarDongsu Park <dongsu.park@profitbricks.com>
      Tested-by: default avatarDongsu Park <dongsu.park@profitbricks.com>
      Signed-off-by: default avatarMing Lei <ming.lei@canonical.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      df0e5109
    • Mike Christie's avatar
      SCSI: add 1024 max sectors black list flag · bda69f1a
      Mike Christie authored
      [ Upstream commit 35e9a9f9 ]
      
      This works around a issue with qnap iscsi targets not handling large IOs
      very well.
      
      The target returns:
      
      VPD INQUIRY: Block limits page (SBC)
        Maximum compare and write length: 1 blocks
        Optimal transfer length granularity: 1 blocks
        Maximum transfer length: 4294967295 blocks
        Optimal transfer length: 4294967295 blocks
        Maximum prefetch, xdread, xdwrite transfer length: 0 blocks
        Maximum unmap LBA count: 8388607
        Maximum unmap block descriptor count: 1
        Optimal unmap granularity: 16383
        Unmap granularity alignment valid: 0
        Unmap granularity alignment: 0
        Maximum write same length: 0xffffffff blocks
        Maximum atomic transfer length: 0
        Atomic alignment: 0
        Atomic transfer length granularity: 0
      
      and it is *sometimes* able to handle at least one IO of size up to 8 MB. We
      have seen in traces where it will sometimes work, but other times it
      looks like it fails and it looks like it returns failures if we send
      multiple large IOs sometimes. Also it looks like it can return 2 different
      errors. It will sometimes send iscsi reject errors indicating out of
      resources or it will send invalid cdb illegal requests check conditions.
      And then when it sends iscsi rejects it does not seem to handle retries
      when there are command sequence holes, so I could not just add code to
      try and gracefully handle that error code.
      
      The problem is that we do not have a good contact for the company,
      so we are not able to determine under what conditions it returns
      which error and why it sometimes works.
      
      So, this patch just adds a new black list flag to set targets like this to
      the old max safe sectors of 1024. The max_hw_sectors changes added in 3.19
      caused this regression, so I also ccing stable.
      Reported-by: default avatarChristian Hesse <list@eworm.de>
      Signed-off-by: default avatarMike Christie <michaelc@cs.wisc.edu>
      Cc: stable@vger.kernel.org
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJames Bottomley <JBottomley@Odin.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      bda69f1a
  4. 04 Aug, 2015 34 commits