Commit 6b0b2d9a authored by Suravee Suthikulpanit's avatar Suravee Suthikulpanit Committed by Joerg Roedel
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iommu/amd: Fix I/O page table memory leak 



The current logic updates the I/O page table mode for the domain
before calling the logic to free memory used for the page table.
This results in IOMMU page table memory leak, and can be observed
when launching VM w/ pass-through devices.

Fix by freeing the memory used for page table before updating the mode.

Cc: Joerg Roedel <joro@8bytes.org>
Reported-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
Tested-by: default avatarDaniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: default avatarSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Fixes: e42ba063 ("iommu/amd: Restructure code for freeing page table")
Link: https://lore.kernel.org/all/20220118194720.urjgi73b7c3tq2o6@oracle.com/
Link: https://lore.kernel.org/r/20220210154745.11524-1-suravee.suthikulpanit@amd.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 5ce97f4e

drivers/iommu/amd/io_pgtable.c

+6 −6
Original line number Diff line number Diff line
@@ -492,18 +492,18 @@ static void v1_free_pgtable(struct io_pgtable *iop) 


	dom = container_of(pgtable, struct protection_domain, iop);



	/* Update data structure */

	amd_iommu_domain_clr_pt_root(dom);



	/* Make changes visible to IOMMUs */

	amd_iommu_domain_update(dom);



	/* Page-table is not visible to IOMMU anymore, so free it */

	BUG_ON(pgtable->mode < PAGE_MODE_NONE ||

	       pgtable->mode > PAGE_MODE_6_LEVEL);



	free_sub_pt(pgtable->root, pgtable->mode, &freelist);



	/* Update data structure */

	amd_iommu_domain_clr_pt_root(dom);



	/* Make changes visible to IOMMUs */

	amd_iommu_domain_update(dom);



	put_pages_list(&freelist);

}