linux-kernel - Re: [PATCHv4] mm: Don't offset memmap for flatmem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 9 Nov 2015 15:20:58 -0800
From:	Tony Luck <tony.luck@...il.com>
To:	Laura Abbott <labbott@...oraproject.org>
Cc:	Srinivas Kandagatla <srinivas.kandagatla@...aro.org>,
	Vlastimil Babka <vbabka@...e.cz>,
	Bjorn Andersson <bjorn.andersson@...ymobile.com>,
	Laura Abbott <laura@...bott.name>,
	Santosh Shilimkar <ssantosh@...nel.org>,
	Russell King <rmk@....linux.org.uk>,
	Kevin Hilman <khilman@...aro.org>,
	Arnd Bergman <arnd@...db.de>,
	Stephen Boyd <sboyd@...eaurora.org>,
	Andy Gross <agross@...eaurora.org>,
	Mel Gorman <mgorman@...e.de>,
	Steven Rostedt <rostedt@...dmis.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Laura Abbott <lauraa@...eaurora.org>
Subject: Re: [PATCHv4] mm: Don't offset memmap for flatmem

> @@ -4984,9 +4987,9 @@ static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
>          */
>         if (pgdat == NODE_DATA(0)) {
>                 mem_map = NODE_DATA(0)->node_mem_map;
> -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
> +#if defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) || defined(CONFIG_FLATMEM)
>                 if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
> -                       mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
> +                       mem_map -= offset;
>  #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
>         }
>  #endif

This piece breaks ia64.  See the comment earlier in the function
that "ia64 gets its own node_mem_map" ... so we skip the initialization
of offset ... and arrive down here and just subtract "0" from mem_map.

Attached patch fixes ia64 ... does ARM still work if this is applied?

-Tony

View attachment "fixia64.patch" of type "text/x-patch" (1226 bytes)