Commit ee01f112 authored by Ingo Molnar's avatar Ingo Molnar

x86: init memory debugging

debug incorrect/late access to init memory, by permanently unmapping
the init memory ranges. Depends on CONFIG_DEBUG_PAGEALLOC=y.
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 1a487252
......@@ -783,6 +783,16 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
{
unsigned long addr;
#ifdef CONFIG_DEBUG_PAGEALLOC
/*
* If debugging page accesses then do not free this memory but
* mark them not present - any buggy init-section access will
* create a kernel page fault:
*/
printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
begin, PAGE_ALIGN(end));
set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
#else
/*
* We just marked the kernel text read only above, now that
* we are going to free part of that, we need to make that
......@@ -798,6 +808,7 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
totalram_pages++;
}
printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
#endif
}
void free_initmem(void)
......
......@@ -550,6 +550,16 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
if (begin >= end)
return;
/*
* If debugging page accesses then do not free this memory but
* mark them not present - any buggy init-section access will
* create a kernel page fault:
*/
#ifdef CONFIG_DEBUG_PAGEALLOC
printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
begin, PAGE_ALIGN(end));
set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
#else
printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
for (addr = begin; addr < end; addr += PAGE_SIZE) {
ClearPageReserved(virt_to_page(addr));
......@@ -575,6 +585,7 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
set_memory_nx(begin, (end - begin)/PAGE_SIZE);
}
#endif
#endif
}
void free_initmem(void)
......
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