linux/arch/alpha/mm/numa.c
Mike Rapoport 5b5260902a alpha: fix hang caused by the bootmem removal
The conversion of alpha to memblock as the early memory manager caused
boot to hang as described at [1].

The issue is caused because for CONFIG_DISCTONTIGMEM=y case,
memblock_add() is called using memory start PFN that had been rounded
down to the nearest 8Mb and it caused memblock to see more memory that
is actually present in the system.

Besides, memblock allocates memory from high addresses while bootmem was
using low memory, which broke the assumption that early allocations are
always accessible by the hardware.

This patch ensures that memblock_add() is using the correct PFN for the
memory start and forces memblock to use bottom-up allocations.

[1] https://lkml.org/lkml/2018/11/22/1032

Link: http://lkml.kernel.org/r/1543233216-25833-1-git-send-email-rppt@linux.ibm.com
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:44 -08:00

235 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/alpha/mm/numa.c
*
* DISCONTIGMEM NUMA alpha support.
*
* Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/memblock.h>
#include <linux/swap.h>
#include <linux/initrd.h>
#include <linux/pfn.h>
#include <linux/module.h>
#include <asm/hwrpb.h>
#include <asm/pgalloc.h>
#include <asm/sections.h>
pg_data_t node_data[MAX_NUMNODES];
EXPORT_SYMBOL(node_data);
#undef DEBUG_DISCONTIG
#ifdef DEBUG_DISCONTIG
#define DBGDCONT(args...) printk(args)
#else
#define DBGDCONT(args...)
#endif
#define for_each_mem_cluster(memdesc, _cluster, i) \
for ((_cluster) = (memdesc)->cluster, (i) = 0; \
(i) < (memdesc)->numclusters; (i)++, (_cluster)++)
static void __init show_mem_layout(void)
{
struct memclust_struct * cluster;
struct memdesc_struct * memdesc;
int i;
/* Find free clusters, and init and free the bootmem accordingly. */
memdesc = (struct memdesc_struct *)
(hwrpb->mddt_offset + (unsigned long) hwrpb);
printk("Raw memory layout:\n");
for_each_mem_cluster(memdesc, cluster, i) {
printk(" memcluster %2d, usage %1lx, start %8lu, end %8lu\n",
i, cluster->usage, cluster->start_pfn,
cluster->start_pfn + cluster->numpages);
}
}
static void __init
setup_memory_node(int nid, void *kernel_end)
{
extern unsigned long mem_size_limit;
struct memclust_struct * cluster;
struct memdesc_struct * memdesc;
unsigned long start_kernel_pfn, end_kernel_pfn;
unsigned long start, end;
unsigned long node_pfn_start, node_pfn_end;
unsigned long node_min_pfn, node_max_pfn;
int i;
int show_init = 0;
/* Find the bounds of current node */
node_pfn_start = (node_mem_start(nid)) >> PAGE_SHIFT;
node_pfn_end = node_pfn_start + (node_mem_size(nid) >> PAGE_SHIFT);
/* Find free clusters, and init and free the bootmem accordingly. */
memdesc = (struct memdesc_struct *)
(hwrpb->mddt_offset + (unsigned long) hwrpb);
/* find the bounds of this node (node_min_pfn/node_max_pfn) */
node_min_pfn = ~0UL;
node_max_pfn = 0UL;
for_each_mem_cluster(memdesc, cluster, i) {
/* Bit 0 is console/PALcode reserved. Bit 1 is
non-volatile memory -- we might want to mark
this for later. */
if (cluster->usage & 3)
continue;
start = cluster->start_pfn;
end = start + cluster->numpages;
if (start >= node_pfn_end || end <= node_pfn_start)
continue;
if (!show_init) {
show_init = 1;
printk("Initializing bootmem allocator on Node ID %d\n", nid);
}
printk(" memcluster %2d, usage %1lx, start %8lu, end %8lu\n",
i, cluster->usage, cluster->start_pfn,
cluster->start_pfn + cluster->numpages);
if (start < node_pfn_start)
start = node_pfn_start;
if (end > node_pfn_end)
end = node_pfn_end;
if (start < node_min_pfn)
node_min_pfn = start;
if (end > node_max_pfn)
node_max_pfn = end;
}
if (mem_size_limit && node_max_pfn > mem_size_limit) {
static int msg_shown = 0;
if (!msg_shown) {
msg_shown = 1;
printk("setup: forcing memory size to %ldK (from %ldK).\n",
mem_size_limit << (PAGE_SHIFT - 10),
node_max_pfn << (PAGE_SHIFT - 10));
}
node_max_pfn = mem_size_limit;
}
if (node_min_pfn >= node_max_pfn)
return;
/* Update global {min,max}_low_pfn from node information. */
if (node_min_pfn < min_low_pfn)
min_low_pfn = node_min_pfn;
if (node_max_pfn > max_low_pfn)
max_pfn = max_low_pfn = node_max_pfn;
#if 0 /* we'll try this one again in a little while */
/* Cute trick to make sure our local node data is on local memory */
node_data[nid] = (pg_data_t *)(__va(node_min_pfn << PAGE_SHIFT));
#endif
printk(" Detected node memory: start %8lu, end %8lu\n",
node_min_pfn, node_max_pfn);
DBGDCONT(" DISCONTIG: node_data[%d] is at 0x%p\n", nid, NODE_DATA(nid));
/* Find the bounds of kernel memory. */
start_kernel_pfn = PFN_DOWN(KERNEL_START_PHYS);
end_kernel_pfn = PFN_UP(virt_to_phys(kernel_end));
if (!nid && (node_max_pfn < end_kernel_pfn || node_min_pfn > start_kernel_pfn))
panic("kernel loaded out of ram");
memblock_add(PFN_PHYS(node_min_pfn),
(node_max_pfn - node_min_pfn) << PAGE_SHIFT);
/* Zone start phys-addr must be 2^(MAX_ORDER-1) aligned.
Note that we round this down, not up - node memory
has much larger alignment than 8Mb, so it's safe. */
node_min_pfn &= ~((1UL << (MAX_ORDER-1))-1);
NODE_DATA(nid)->node_start_pfn = node_min_pfn;
NODE_DATA(nid)->node_present_pages = node_max_pfn - node_min_pfn;
node_set_online(nid);
}
void __init
setup_memory(void *kernel_end)
{
unsigned long kernel_size;
int nid;
show_mem_layout();
nodes_clear(node_online_map);
min_low_pfn = ~0UL;
max_low_pfn = 0UL;
for (nid = 0; nid < MAX_NUMNODES; nid++)
setup_memory_node(nid, kernel_end);
kernel_size = virt_to_phys(kernel_end) - KERNEL_START_PHYS;
memblock_reserve(KERNEL_START_PHYS, kernel_size);
#ifdef CONFIG_BLK_DEV_INITRD
initrd_start = INITRD_START;
if (initrd_start) {
extern void *move_initrd(unsigned long);
initrd_end = initrd_start+INITRD_SIZE;
printk("Initial ramdisk at: 0x%p (%lu bytes)\n",
(void *) initrd_start, INITRD_SIZE);
if ((void *)initrd_end > phys_to_virt(PFN_PHYS(max_low_pfn))) {
if (!move_initrd(PFN_PHYS(max_low_pfn)))
printk("initrd extends beyond end of memory "
"(0x%08lx > 0x%p)\ndisabling initrd\n",
initrd_end,
phys_to_virt(PFN_PHYS(max_low_pfn)));
} else {
nid = kvaddr_to_nid(initrd_start);
memblock_reserve(virt_to_phys((void *)initrd_start),
INITRD_SIZE);
}
}
#endif /* CONFIG_BLK_DEV_INITRD */
}
void __init paging_init(void)
{
unsigned int nid;
unsigned long zones_size[MAX_NR_ZONES] = {0, };
unsigned long dma_local_pfn;
/*
* The old global MAX_DMA_ADDRESS per-arch API doesn't fit
* in the NUMA model, for now we convert it to a pfn and
* we interpret this pfn as a local per-node information.
* This issue isn't very important since none of these machines
* have legacy ISA slots anyways.
*/
dma_local_pfn = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
for_each_online_node(nid) {
unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_present_pages;
if (dma_local_pfn >= end_pfn - start_pfn)
zones_size[ZONE_DMA] = end_pfn - start_pfn;
else {
zones_size[ZONE_DMA] = dma_local_pfn;
zones_size[ZONE_NORMAL] = (end_pfn - start_pfn) - dma_local_pfn;
}
node_set_state(nid, N_NORMAL_MEMORY);
free_area_init_node(nid, zones_size, start_pfn, NULL);
}
/* Initialize the kernel's ZERO_PGE. */
memset((void *)ZERO_PGE, 0, PAGE_SIZE);
}