Revision a9fc4340aee041dd186d1fb8f1b5d1e9caf28212 authored by Dexuan Cui on 07 May 2019, 07:46:55 UTC, committed by Sasha Levin on 20 August 2019, 16:49:57 UTC
In the case of X86_PAE, unsigned long is u32, but the physical address type
should be u64. Due to the bug here, the netvsc driver can not load
successfully, and sometimes the VM can panic due to memory corruption (the
hypervisor writes data to the wrong location).

Fixes: 6ba34171bcbd ("Drivers: hv: vmbus: Remove use of slow_virt_to_phys()")
Cc: stable@vger.kernel.org
Cc: Michael Kelley <mikelley@microsoft.com>
Reported-and-tested-by: Juliana Rodrigueiro <juliana.rodrigueiro@intra2net.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by:  Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
1 parent 89eb4d8
Raw File
iommu-helper.c
// SPDX-License-Identifier: GPL-2.0
/*
 * IOMMU helper functions for the free area management
 */

#include <linux/bitmap.h>
#include <linux/iommu-helper.h>

unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
			       unsigned long start, unsigned int nr,
			       unsigned long shift, unsigned long boundary_size,
			       unsigned long align_mask)
{
	unsigned long index;

	/* We don't want the last of the limit */
	size -= 1;
again:
	index = bitmap_find_next_zero_area(map, size, start, nr, align_mask);
	if (index < size) {
		if (iommu_is_span_boundary(index, nr, shift, boundary_size)) {
			start = ALIGN(shift + index, boundary_size) - shift;
			goto again;
		}
		bitmap_set(map, index, nr);
		return index;
	}
	return -1;
}
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