From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Cotte-Barrot Date: Tue, 05 Dec 2006 09:58:39 +0000 Subject: Re: 05e0caad3b7bd0d0fbeff980bca22f186241a501 breaks ia64 kdump Message-Id: <457542CF.5060905@bull.net> List-Id: References: <20061026075951.GA30910@verge.net.au> In-Reply-To: <20061026075951.GA30910@verge.net.au> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Why the above Bob's patch not included in 2.6.19 ? It is still needed to boot ia64 platform. Mel Gorman wrote: >>>As you say, it's not clear why the normal discontig kernel boots because >>>the regions should have been skipped by add_active_range(). >>> >> >> I think that depends on the init value of memmap, if they are all zero, >> free_pages_check will be happy and not report any thing. So I guess we may >> see this bug in normal kernel with a warm reboot, or with a machine which >> PROM does not clear memory to all zero. > > It could have been just luck. See more below > >> >>>Try your patch and see does it work for kdump. It should work fine in the >>>normal case because at very worst, slightly more memmap is allocated than >>>is strictly required. >>> >> >> It works for kdump. >> > > Can you try out the patch below please as a possibly simplier alternative? It's > a patch from Bob Picco that addresses a similar problem with initmem on a > kernel booting as normal. The only difference between Bob's original patch > and this one is the addition of the CONFIG_KEXEC stuff from your patch. It > survived a simply boot test. > > Thanks > >>>>Begin Bob's patch > > While pursuing and unrelated issue with 64Mb granules I noticed a problem > related to inconsistent use of add_active_range. There doesn't appear any > reason to me why FLATMEM versus DISCONTIG_MEM should register memory > to add_active_range with different code. So I've changed the code into > a common implementation. > > The other subtle issue fixed by this patch was calling add_active_range > in count_node_pages before granule aligning is performed. We were lucky with > 16MB granules but not so with 64MB granules. count_node_pages has reserved > regions filtered out and as a consequence linked kernel text and data > aren't covered by calls to count_node_pages. So linked kernel regions > wasn't reported to add_active_regions. This resulted in free_initmem causing > numerous bad_page reports. This won't occur with this patch because now > all known memory regions are reported by register_active_ranges. > > Acked-by: Mel Gorman > Signed-off-by: Bob Picco > > arch/ia64/mm/contig.c | 3 +-- > arch/ia64/mm/discontig.c | 4 +++- > arch/ia64/mm/init.c | 24 +++++++++++++++++------- > include/asm-ia64/meminit.h | 3 ++- > 4 files changed, 23 insertions(+), 11 deletions(-) > > diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.19-rc5-clean/arch/ia64/mm/contig.c linux-2.6.19-rc5-register_all_memory/arch/ia64/mm/contig.c > --- linux-2.6.19-rc5-clean/arch/ia64/mm/contig.c 2006-11-08 02:24:20.000000000 +0000 > +++ linux-2.6.19-rc5-register_all_memory/arch/ia64/mm/contig.c 2006-11-16 15:29:31.000000000 +0000 > @@ -226,7 +226,6 @@ void __init > paging_init (void) > { > unsigned long max_dma; > - unsigned long nid = 0; > unsigned long max_zone_pfns[MAX_NR_ZONES]; > > num_physpages = 0; > @@ -238,7 +237,7 @@ paging_init (void) > max_zone_pfns[ZONE_NORMAL] = max_low_pfn; > > #ifdef CONFIG_VIRTUAL_MEM_MAP > - efi_memmap_walk(register_active_ranges, &nid); > + efi_memmap_walk(register_active_ranges, NULL); > efi_memmap_walk(find_largest_hole, (u64 *)&max_gap); > if (max_gap < LARGE_GAP) { > vmem_map = (struct page *) 0; > diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.19-rc5-clean/arch/ia64/mm/discontig.c linux-2.6.19-rc5-register_all_memory/arch/ia64/mm/discontig.c > --- linux-2.6.19-rc5-clean/arch/ia64/mm/discontig.c 2006-11-08 02:24:20.000000000 +0000 > +++ linux-2.6.19-rc5-register_all_memory/arch/ia64/mm/discontig.c 2006-11-16 15:29:31.000000000 +0000 > @@ -473,6 +473,9 @@ void __init find_memory(void) > node_clear(node, memory_less_mask); > mem_data[node].min_pfn = ~0UL; > } > + > + efi_memmap_walk(register_active_ranges, NULL); > + > /* > * Initialize the boot memory maps in reverse order since that's > * what the bootmem allocator expects > @@ -654,7 +657,6 @@ static __init int count_node_pages(unsig > { > unsigned long end = start + len; > > - add_active_range(node, start >> PAGE_SHIFT, end >> PAGE_SHIFT); > mem_data[node].num_physpages += len >> PAGE_SHIFT; > if (start <= __pa(MAX_DMA_ADDRESS)) > mem_data[node].num_dma_physpages +> diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.19-rc5-clean/arch/ia64/mm/init.c linux-2.6.19-rc5-register_all_memory/arch/ia64/mm/init.c > --- linux-2.6.19-rc5-clean/arch/ia64/mm/init.c 2006-11-08 02:24:20.000000000 +0000 > +++ linux-2.6.19-rc5-register_all_memory/arch/ia64/mm/init.c 2006-11-16 15:33:25.000000000 +0000 > @@ -594,18 +594,28 @@ find_largest_hole (u64 start, u64 end, v > return 0; > } > > +#endif /* CONFIG_VIRTUAL_MEM_MAP */ > + > int __init > -register_active_ranges(u64 start, u64 end, void *nid) > +register_active_ranges(u64 start, u64 end, void *arg) > { > - BUG_ON(nid = NULL); > - BUG_ON(*(unsigned long *)nid >= MAX_NUMNODES); > + int nid = paddr_to_nid(__pa(start)); > + > + if (nid < 0) > + nid = 0; > > - add_active_range(*(unsigned long *)nid, > - __pa(start) >> PAGE_SHIFT, > - __pa(end) >> PAGE_SHIFT); > +#ifdef CONFIG_KEXEC > + if (start > crashk_res.start && start < crashk_res.end) > + start = max(start, crashk_res.end); > + if (end > crashk_res.start && end < crashk_res.end) > + end = min(end, crashk_res.start); > +#endif > + > + if (start < end) > + add_active_range(nid, __pa(start) >> PAGE_SHIFT, > + __pa(end) >> PAGE_SHIFT); > return 0; > } > -#endif /* CONFIG_VIRTUAL_MEM_MAP */ > > static int __init > count_reserved_pages (u64 start, u64 end, void *arg) > diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.19-rc5-clean/include/asm-ia64/meminit.h linux-2.6.19-rc5-register_all_memory/include/asm-ia64/meminit.h > --- linux-2.6.19-rc5-clean/include/asm-ia64/meminit.h 2006-11-08 02:24:20.000000000 +0000 > +++ linux-2.6.19-rc5-register_all_memory/include/asm-ia64/meminit.h 2006-11-16 15:29:31.000000000 +0000 > @@ -50,12 +50,13 @@ extern void efi_memmap_init(unsigned lon > > #define IGNORE_PFN0 1 /* XXX fix me: ignore pfn 0 until TLB miss handler is updated... */ > > +extern int register_active_ranges (u64 start, u64 end, void *arg); > + > #ifdef CONFIG_VIRTUAL_MEM_MAP > # define LARGE_GAP 0x40000000 /* Use virtual mem map if hole is > than this */ > extern unsigned long vmalloc_end; > extern struct page *vmem_map; > extern int find_largest_hole (u64 start, u64 end, void *arg); > - extern int register_active_ranges (u64 start, u64 end, void *arg); > extern int create_mem_map_page_table (u64 start, u64 end, void *arg); > extern int vmemmap_find_next_valid_pfn(int, int); > #else > -- +======+============+=================+ | |\/\/\/| | | | | | | |Christian Cotte-Barrot |org. :BULL/ | | | (~)(o) |Bull S.A. |office:FREC/B1-401 | | C _) |1, rue de Provence |mailto: | | | ,___| |B.P. 208 | Christian.Cotte-Barrot@bull.net| | | / |38432 ECHIROLLES CEDEX |phone :+33 (0)476297725 (229 7725)| | /----\ |FRANCE |fax :+33 (0)476297518 (229 7518)| +======+============+=================+