• Rick Edgecombe's avatar
    mm/vmalloc: Fix calculation of direct map addr range · 8e41f872
    Rick Edgecombe authored
    The calculation of the direct map address range to flush was wrong.
    This could cause the RO direct map alias to not get flushed. Today
    this shouldn't be a problem because this flush is only needed on x86
    right now and the spurious fault handler will fix cached RO->RW
    translations. In the future though, it could cause the permissions
    to remain RO in the TLB for the direct map alias, and then the page
    would return from the page allocator to some other component as RO
    and cause a crash.
    
    So fix fix the address range calculation so the flush will include the
    direct map range.
    Signed-off-by: default avatarRick Edgecombe <rick.p.edgecombe@intel.com>
    Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    Cc: Andy Lutomirski <luto@kernel.org>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Dave Hansen <dave.hansen@intel.com>
    Cc: David S. Miller <davem@davemloft.net>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Meelis Roos <mroos@linux.ee>
    Cc: Nadav Amit <namit@vmware.com>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Fixes: 868b104d ("mm/vmalloc: Add flag for freeing of special permsissions")
    Link: https://lkml.kernel.org/r/20190527211058.2729-2-rick.p.edgecombe@intel.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    8e41f872
vmalloc.c 87 KB