From 97729b653de52ba98e08732dd8855586e37a3a31 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Wed, 12 May 2021 13:18:23 -0700 Subject: xen/swiotlb: check if the swiotlb has already been initialized xen_swiotlb_init calls swiotlb_late_init_with_tbl, which fails with -ENOMEM if the swiotlb has already been initialized. Add an explicit check io_tlb_default_mem != NULL at the beginning of xen_swiotlb_init. If the swiotlb is already initialized print a warning and return -EEXIST. On x86, the error propagates. On ARM, we don't actually need a special swiotlb buffer (yet), any buffer would do. So ignore the error and continue. CC: boris.ostrovsky@oracle.com CC: jgross@suse.com Signed-off-by: Stefano Stabellini Reviewed-by: Boris Ostrovsky Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20210512201823.1963-3-sstabellini@kernel.org Signed-off-by: Juergen Gross --- arch/arm/xen/mm.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'arch/arm/xen') diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c index 223b1151fd7d..a7e54a087b80 100644 --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -138,9 +138,15 @@ void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) static int __init xen_mm_init(void) { struct gnttab_cache_flush cflush; + int rc; + if (!xen_swiotlb_detect()) return 0; - xen_swiotlb_init(); + + rc = xen_swiotlb_init(); + /* we can work with the default swiotlb */ + if (rc < 0 && rc != -EEXIST) + return rc; cflush.op = 0; cflush.a.dev_bus_addr = 0; -- cgit v1.2.3