iommu/amd: Do not loop forever when trying to increase address space (5b8a9a04) · Commits · 戴 / test

When increase_address_space() fails to allocate memory, alloc_pte() will call it again until it succeeds. Do not loop forever while trying to increase the address space and just return an error instead. Signed-off-by:

Joerg Roedel <jroedel@suse.de> Tested-by:

Qian Cai <cai@lca.pw> Link: https://lore.kernel.org/r/20200504125413.16798-3-joro@8bytes.org Signed-off-by:

Joerg Roedel <jroedel@suse.de>

drivers/iommu/amd_iommu.c

+12 −1

Original line number	Diff line number	Diff line
		@@ -1489,8 +1489,19 @@ static u64 alloc_pte(struct protection_domain domain,
		amd_iommu_domain_get_pgtable(domain, &pgtable);

		while (address > PM_LEVEL_SIZE(pgtable.mode)) {
		updated = increase_address_space(domain, address, gfp) \|\| updated;
		bool upd = increase_address_space(domain, address, gfp);

		/* Read new values to check if update was successful */
		amd_iommu_domain_get_pgtable(domain, &pgtable);

		/*
		* Return an error if there is no memory to update the
		* page-table.
		*/
		if (!upd && (address > PM_LEVEL_SIZE(pgtable.mode)))
		return NULL;

		updated = updated \|\| upd;
		}

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