Quoting r. Hugh Dickins <[email protected]>: > Subject: Re: [openib-general] Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support > > On Thu, 11 Aug 2005, Gleb Natapov wrote: > > What about the idea that was floating around about new VM flag that will > > instruct kernel to copy pages belonging to the vma on fork instead of mark > > them as cow? > > It's a pretty good idea, and thanks for reminding us of it. > > It suffers from the general difficulty with fixes within get_user_pages, > that we need down_write(&mm->mmap_sem) to split_vma, and even just to > update vm_flags, whereas get_user_pages is entered with down_read. No, the idea is to let the application (or a library that it loades) change this flag by means of some system call. Something like MADV_COPYONFORK, in addition to MADV_DONTCOPY. -- MST - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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- [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
- From: "Michael S. Tsirkin" <[email protected]>
- Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
- From: Hugh Dickins <[email protected]>
- Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
- From: "Michael S. Tsirkin" <[email protected]>
- Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
- From: Hugh Dickins <[email protected]>
- Re: [openib-general] Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
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- Re: [openib-general] Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
- From: Hugh Dickins <[email protected]>
- Re: [openib-general] Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
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- Re: [openib-general] Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
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- Re: [openib-general] Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
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- Re: [openib-general] Re: [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
- From: Hugh Dickins <[email protected]>
- [PATCH repost] PROT_DONTCOPY: ifiniband uverbs fork support
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