Revision a6335fa11e08fc386740557b2a4c1b7ff34bc499 authored by Alexander Sverdlin on 02 July 2015, 15:16:01 UTC, committed by Ralf Baechle on 09 July 2015, 09:02:59 UTC
Commit f9a7febd leads to a fact that mapstart and therefore a page bitmap for
bootmem allocator immediately follows initrd_end. This doesn't always work
well on Octeon, where there are holes in PFN ranges (refer to 5b3b1688 and
4MB-aligned PFN allocation). Depending on the inird location it could happen,
that mapstart would be in an area not allocated by plat_mem_setup() in
arch/mips/cavium-octeon/setup.c, but in the alignment hole between initrd and
the next PFN area. Later on this memory will be unconditionally made available
to buddy allocator at the end of free_all_bootmem_core() (mm/bootmem.c).
All of this results in Linux using the memory not designated for Linux in
Octeon's plat_mem_setup(), which in turn means corruption of the memory used
by another OS/baremetal code on the same SoC.

It doesn't look to me as a problem of Octeon platform code, but rather as an
inability of f9a7febd to deal correctly with the fragmented memory-mappings.
Proposed fix moves the check for initrd address to the same calculation-loop
in bootmem_init() (arch/mips/kernel/setup.c), which also accounts for kernel
code location. This should result in mapstart located starting from the first
PFN area after kernel code AND initrd.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: linux-mips@linux-mips.org
Cc: David Daney <david.daney@cavium.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: Joe Perches <joe@perches.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Yusuf Khan <yusuf.khan@nokia.com>
Cc: Michael Kreuzer <michael.kreuzer@nokia.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Patchwork: https://patchwork.linux-mips.org/patch/10594/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1 parent 7928eb0
Raw File
br_private_stp.h
/*
 *	Linux ethernet bridge
 *
 *	Authors:
 *	Lennert Buytenhek		<buytenh@gnu.org>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#ifndef _BR_PRIVATE_STP_H
#define _BR_PRIVATE_STP_H

#define BPDU_TYPE_CONFIG 0
#define BPDU_TYPE_TCN 0x80

/* IEEE 802.1D-1998 timer values */
#define BR_MIN_HELLO_TIME	(1*HZ)
#define BR_MAX_HELLO_TIME	(10*HZ)

#define BR_MIN_FORWARD_DELAY	(2*HZ)
#define BR_MAX_FORWARD_DELAY	(30*HZ)

#define BR_MIN_MAX_AGE		(6*HZ)
#define BR_MAX_MAX_AGE		(40*HZ)

#define BR_MIN_PATH_COST	1
#define BR_MAX_PATH_COST	65535

struct br_config_bpdu {
	unsigned int	topology_change:1;
	unsigned int	topology_change_ack:1;
	bridge_id	root;
	int		root_path_cost;
	bridge_id	bridge_id;
	port_id		port_id;
	int		message_age;
	int		max_age;
	int		hello_time;
	int		forward_delay;
};

/* called under bridge lock */
static inline int br_is_designated_port(const struct net_bridge_port *p)
{
	return !memcmp(&p->designated_bridge, &p->br->bridge_id, 8) &&
		(p->designated_port == p->port_id);
}


/* br_stp.c */
void br_become_root_bridge(struct net_bridge *br);
void br_config_bpdu_generation(struct net_bridge *);
void br_configuration_update(struct net_bridge *);
void br_port_state_selection(struct net_bridge *);
void br_received_config_bpdu(struct net_bridge_port *p,
			     const struct br_config_bpdu *bpdu);
void br_received_tcn_bpdu(struct net_bridge_port *p);
void br_transmit_config(struct net_bridge_port *p);
void br_transmit_tcn(struct net_bridge *br);
void br_topology_change_detection(struct net_bridge *br);

/* br_stp_bpdu.c */
void br_send_config_bpdu(struct net_bridge_port *, struct br_config_bpdu *);
void br_send_tcn_bpdu(struct net_bridge_port *);

#endif
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