Commit f5ec6723 authored Jul 27, 2020 by Roger Pau Monne Committed by Juergen Gross Aug 03, 2020

Revert "xen/balloon: Fix crash when ballooning on x86 32 bit PAE"



This reverts commit dfd74a1e.

This has been fixed by commit dca4436d which added the out
of bounds check to __add_memory, so that trying to add blocks past
MAX_PHYSMEM_BITS will fail.

Note the check in the Xen balloon driver was bogus anyway, as it
checked the start address of the resource, but it should instead test
the end address to assert the whole resource falls below
MAX_PHYSMEM_BITS.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200727091342.52325-4-roger.pau@citrix.com


Signed-off-by: Juergen Gross <jgross@suse.com>

parent 88a479ff

drivers/xen/balloon.c

+0 −14

Original line number	Diff line number	Diff line
		@@ -266,20 +266,6 @@ static struct resource *additional_memory_resource(phys_addr_t size)
		return NULL;
		}

		#ifdef CONFIG_SPARSEMEM
		{
		unsigned long limit = 1UL << (MAX_PHYSMEM_BITS - PAGE_SHIFT);
		unsigned long pfn = res->start >> PAGE_SHIFT;

		if (pfn > limit) {
		pr_err("New System RAM resource outside addressable RAM (%lu > %lu)\n",
		pfn, limit);
		release_memory_resource(res);
		return NULL;
		}
		}
		#endif

		return res;
		}

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