Re: [PATCHv6 5/7] mm: make compound_head() robust

2015-09-15 Thread Paul E. McKenney
On Tue, Sep 15, 2015 at 01:28:13PM +0300, Kirill A. Shutemov wrote: > Hugh has pointed that compound_head() call can be unsafe in some > context. There's one example: > > CPU0CPU1 > > isolate_migratepages_block() > page_count() > compound_head() >

[PATCHv6 5/7] mm: make compound_head() robust

2015-09-15 Thread Kirill A. Shutemov
Hugh has pointed that compound_head() call can be unsafe in some context. There's one example: CPU0CPU1 isolate_migratepages_block() page_count() compound_head() !!PageTail() == true put_page()

[PATCHv6 5/7] mm: make compound_head() robust

2015-09-15 Thread Kirill A. Shutemov
Hugh has pointed that compound_head() call can be unsafe in some context. There's one example: CPU0CPU1 isolate_migratepages_block() page_count() compound_head() !!PageTail() == true put_page()

Re: [PATCHv6 5/7] mm: make compound_head() robust

2015-09-15 Thread Paul E. McKenney
On Tue, Sep 15, 2015 at 01:28:13PM +0300, Kirill A. Shutemov wrote: > Hugh has pointed that compound_head() call can be unsafe in some > context. There's one example: > > CPU0CPU1 > > isolate_migratepages_block() > page_count() > compound_head() >