Date: Thu, 5 Jul 2018 16:43:16 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r336001 - head/sys/vm Message-ID: <201807051643.w65GhGFQ049659@repo.freebsd.org>
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Author: kib Date: Thu Jul 5 16:43:15 2018 New Revision: 336001 URL: https://svnweb.freebsd.org/changeset/base/336001 Log: Copyout(9) on 4/4 i386 needs correct vm_page_array[]. On the 4/4 i386, copyout(9) may need to call pmap_extract_and_hold() on arbitrary userspace mapping. If the mapping is backed by the non-managed cdev pager or by the sg pager, on dense configs we might access arbitrary element of vm_page_array[], in particular, not corresponding to a page from the memory segment. Initialize such pages as fictitious with the corresponding physical address. Reported by: bde Reviewed by: alc, markj (previous version) Sponsored by: The FreeBSD Foundation Differential revision: https://reviews.freebsd.org/D16085 Modified: head/sys/vm/vm_page.c Modified: head/sys/vm/vm_page.c ============================================================================== --- head/sys/vm/vm_page.c Thu Jul 5 16:40:20 2018 (r336000) +++ head/sys/vm/vm_page.c Thu Jul 5 16:43:15 2018 (r336001) @@ -551,6 +551,9 @@ vm_page_startup(vm_offset_t vaddr) vm_paddr_t biggestsize, last_pa, pa; u_long pagecount; int biggestone, i, segind; +#if defined(__i386__) && defined(VM_PHYSSEG_DENSE) + long ii; +#endif biggestsize = 0; biggestone = 0; @@ -789,6 +792,13 @@ vm_page_startup(vm_offset_t vaddr) * Initialize the page structures and add every available page to the * physical memory allocator's free lists. */ +#if defined(__i386__) && defined(VM_PHYSSEG_DENSE) + for (ii = 0; ii < vm_page_array_size; ii++) { + m = &vm_page_array[ii]; + vm_page_init_page(m, (first_page + ii) << PAGE_SHIFT, 0); + m->flags = PG_FICTITIOUS; + } +#endif vm_cnt.v_page_count = 0; for (segind = 0; segind < vm_phys_nsegs; segind++) { seg = &vm_phys_segs[segind];
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