• Linus Torvalds's avatar
    Merge branch 'for-linus-clk' of git://ftp.arm.linux.org.uk/~rmk/linux-arm · 2ad7b44f
    Linus Torvalds authored
    Pull clkdev updates from Russell King:
     "This series addresses some breakage in clkdev caused by a previous
      patch set from the clk tree which introduced per-user clk structures.
      This basically renamed the existing 'struct clk' to 'struct clk_hw',
      and introduced a new 'struct clk'.
    
      This change will break anyone using clk_add_alias() with the common
      clk code enabled.  Thankfully, the intersection of users of
      clk_add_alias() and those using the common clk code is practically
      zero, but this is something which should be fixed to keep the code
      sane.
    
      The problem is that clk_add_alias() does this:
    
            r = clk_get(...);
            l = clkdev_alloc(r, ...);
            clk_put(...);
    
      which causes the alias to store a pointer to 'r', which has been
      freed.
    
      The original patch set tried to work around this problem incorrectly -
      at clk_get() time, it tried to convert the struct clk to a struct
      clk_hw, and then creating a new struct clk from that.  Clearly, if the
      original struct clk has been freed, then we have a use-after-free bug.
    
      We have other places in the tree which do something similar, so this
      series also addresses those locations too.
    
      This series addresses this problem by converting clkdev to store and
      use the clk_hw pointer.  This allows clk_get() to only have to create
      it's per-user struct clk from the clk_hw.  We can also get to the
      desired clk_hw at clk_add_alias() or clk lookup creation time, when
      the struct clk is "alive".
    
      We also perform some cleanups of the code:
    
       - replacing looped calls to clkdev_add() with clkdev_add_table()
    
       - replacing open-coded lookup allocation (which should have been
         using clkdev_alloc()) and subsequent clkdev_add() with
         clkdev_create()
    
       - replacing open-coded clk_add_alias() with clk_add_alias()"
    
    * 'for-linus-clk' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
      clk: s2mps11: use clkdev_create()
      ASoC: migor: use clkdev_create()
      ARM: omap2: use clkdev_add_alias()
      ARM: omap2: use clkdev_create()
      ARM: orion: use clkdev_create()
      ARM: lpc32xx: convert to use clkdev_add_table()
      SH: use clkdev_add_table()
      clkdev: add clkdev_create() helper
      clkdev: const-ify connection id to clk_add_alias()
      clkdev: get rid of redundant clk_add_alias() prototype in linux/clk.h
      clkdev: drop __init from clkdev_add_table()
      clk: update clk API documentation to clarify clk_round_rate()
      clkdev: use clk_hw internally
    2ad7b44f
lubbock.c 13.7 KB