From ce44fd015e55d0ecc47c160fb5ce69070aa4991b Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Tue, 20 Aug 2019 13:22:55 +0100 Subject: [PATCH] xen/arm: iommu: Panic if not all IOMMUs are initialized At the moment, the platform can come up with only part of the IOMMUs initialized. This could lead to a failure later on when building the hardware domain or even trying to assign a device to a guest. To avoid unwanted behavior, Xen will not continue if one of the IOMMUs has not been initialized correctly. [stefano: fix typo in comment, add '\n' to panic message] Signed-off-by: Julien Grall Signed-off-by: Stefano Stabellini Reviewed-by: Stefano Stabellini Tested-by: Oleksandr Tyshchenko --- xen/arch/arm/setup.c | 5 ++++- xen/drivers/passthrough/arm/iommu.c | 8 ++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c index 077b8d02a0..581b262655 100644 --- a/xen/arch/arm/setup.c +++ b/xen/arch/arm/setup.c @@ -784,6 +784,7 @@ void __init start_xen(unsigned long boot_phys_offset, .max_grant_frames = gnttab_dom0_frames(), .max_maptrack_frames = opt_max_maptrack_frames, }; + int rc; dcache_line_bytes = read_dcache_line_bytes(); @@ -923,7 +924,9 @@ void __init start_xen(unsigned long boot_phys_offset, setup_virt_paging(); - iommu_setup(); + rc = iommu_setup(); + if ( !iommu_enabled && rc != -ENODEV ) + panic("Couldn't configure correctly all the IOMMUs.\n"); do_initcalls(); diff --git a/xen/drivers/passthrough/arm/iommu.c b/xen/drivers/passthrough/arm/iommu.c index 9cfb589083..2678ef5c01 100644 --- a/xen/drivers/passthrough/arm/iommu.c +++ b/xen/drivers/passthrough/arm/iommu.c @@ -52,6 +52,14 @@ int __init iommu_hardware_setup(void) rc = device_init(np, DEVICE_IOMMU, NULL); if ( !rc ) num_iommus++; + /* + * Ignore the following error codes: + * - EBADF: Indicate the current is not an IOMMU + * - ENODEV: The IOMMU is not present or cannot be used by + * Xen. + */ + else if ( rc != -EBADF && rc != -ENODEV ) + return rc; } return ( num_iommus > 0 ) ? 0 : -ENODEV; -- 2.39.5