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Revision f32393c943e297b8ae180c8f83d81a156c7d0412 authored by Nathan Fontenot on 30 April 2015, 01:42:06 UTC, committed by Michael Ellerman on 01 May 2015, 03:47:24 UTC 
powerpc/pseries: Correct cpu affinity for dlpar added cpus
 
The incorrect ordering of operations during cpu dlpar add results in invalid
affinity for the cpu being added. The ibm,associativity property in the
device tree is populated with all zeroes for the added cpu which results in
invalid affinity mappings and all cpus appear to belong to node 0.

This occurs because rtas configure-connector is called prior to making the
rtas set-indicator calls. Phyp does not assign affinity information
for a cpu until the rtas set-indicator calls are made to set the isolation
and allocation state.

Correct the order of operations to make the rtas set-indicator
calls (done in dlpar_acquire_drc) before calling rtas configure-connector.

Fixes: 1a8061c46c46 ("powerpc/pseries: Add kernel based CPU DLPAR handling")

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1 parent 2fa30fe
Raw File
debug-pagealloc.c 
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/page_ext.h>
#include <linux/poison.h>
#include <linux/ratelimit.h>

static bool page_poisoning_enabled __read_mostly;

static bool need_page_poisoning(void)
{
	if (!debug_pagealloc_enabled())
		return false;

	return true;
}

static void init_page_poisoning(void)
{
	if (!debug_pagealloc_enabled())
		return;

	page_poisoning_enabled = true;
}

struct page_ext_operations page_poisoning_ops = {
	.need = need_page_poisoning,
	.init = init_page_poisoning,
};

static inline void set_page_poison(struct page *page)
{
	struct page_ext *page_ext;

	page_ext = lookup_page_ext(page);
	__set_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
}

static inline void clear_page_poison(struct page *page)
{
	struct page_ext *page_ext;

	page_ext = lookup_page_ext(page);
	__clear_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
}

static inline bool page_poison(struct page *page)
{
	struct page_ext *page_ext;

	page_ext = lookup_page_ext(page);
	return test_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
}

static void poison_page(struct page *page)
{
	void *addr = kmap_atomic(page);

	set_page_poison(page);
	memset(addr, PAGE_POISON, PAGE_SIZE);
	kunmap_atomic(addr);
}

static void poison_pages(struct page *page, int n)
{
	int i;

	for (i = 0; i < n; i++)
		poison_page(page + i);
}

static bool single_bit_flip(unsigned char a, unsigned char b)
{
	unsigned char error = a ^ b;

	return error && !(error & (error - 1));
}

static void check_poison_mem(unsigned char *mem, size_t bytes)
{
	static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 10);
	unsigned char *start;
	unsigned char *end;

	start = memchr_inv(mem, PAGE_POISON, bytes);
	if (!start)
		return;

	for (end = mem + bytes - 1; end > start; end--) {
		if (*end != PAGE_POISON)
			break;
	}

	if (!__ratelimit(&ratelimit))
		return;
	else if (start == end && single_bit_flip(*start, PAGE_POISON))
		printk(KERN_ERR "pagealloc: single bit error\n");
	else
		printk(KERN_ERR "pagealloc: memory corruption\n");

	print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, start,
			end - start + 1, 1);
	dump_stack();
}

static void unpoison_page(struct page *page)
{
	void *addr;

	if (!page_poison(page))
		return;

	addr = kmap_atomic(page);
	check_poison_mem(addr, PAGE_SIZE);
	clear_page_poison(page);
	kunmap_atomic(addr);
}

static void unpoison_pages(struct page *page, int n)
{
	int i;

	for (i = 0; i < n; i++)
		unpoison_page(page + i);
}

void __kernel_map_pages(struct page *page, int numpages, int enable)
{
	if (!page_poisoning_enabled)
		return;

	if (enable)
		unpoison_pages(page, numpages);
	else
		poison_pages(page, numpages);
}
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