From: Joerg Roedel Date: Mon, 4 May 2020 12:54:10 +0000 (+0200) Subject: iommu/amd: Do not loop forever when trying to increase address space X-Git-Tag: v5.15~3905^2~4 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5b8a9a047b6cad361405c7900c1e1cdd378c4589;p=platform%2Fkernel%2Flinux-starfive.git iommu/amd: Do not loop forever when trying to increase address space 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 Tested-by: Qian Cai Link: https://lore.kernel.org/r/20200504125413.16798-3-joro@8bytes.org Signed-off-by: Joerg Roedel --- diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 28229a3..68da484 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -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; }