Messages in this thread |  | | Subject | Re: [PATCH v2 2/2] iommu/vt-d: skip invalid RMRR entries | From | Lu Baolu <> | Date | Wed, 8 Jan 2020 09:27:36 +0800 |
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Hi,
On 1/8/20 3:16 AM, Barret Rhoden via iommu wrote: > The VT-d docs specify requirements for the RMRR entries base and end > (called 'Limit' in the docs) addresses. > > This commit will cause the DMAR processing to skip any RMRR entries that > do not meet these requirements and mark the firmware as tainted, since > the firmware is giving us junk. > > Signed-off-by: Barret Rhoden <brho@google.com> > --- > drivers/iommu/intel-iommu.c | 14 +++++++++++++- > 1 file changed, 13 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index a8bb458845bc..32c3c6338a3d 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -4315,13 +4315,25 @@ static void __init init_iommu_pm_ops(void) > static inline void init_iommu_pm_ops(void) {} > #endif /* CONFIG_PM */ > > +static int rmrr_validity_check(struct acpi_dmar_reserved_memory *rmrr) > +{ > + if ((rmrr->base_address & PAGE_MASK) || > + (rmrr->end_address <= rmrr->base_address) || > + ((rmrr->end_address - rmrr->base_address + 1) & PAGE_MASK)) { > + pr_err(FW_BUG "Broken RMRR base: %#018Lx end: %#018Lx\n", > + rmrr->base_address, rmrr->end_address);
Since you will WARN_TAINT below, do you still want an error message here?
> + return -EINVAL; > + } > + return 0; > +} > + > int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header, void *arg) > { > struct acpi_dmar_reserved_memory *rmrr; > struct dmar_rmrr_unit *rmrru; > > rmrr = (struct acpi_dmar_reserved_memory *)header; > - if (arch_rmrr_sanity_check(rmrr)) { > + if (rmrr_validity_check(rmrr) || arch_rmrr_sanity_check(rmrr)) { > WARN_TAINT(1, TAINT_FIRMWARE_WORKAROUND, > "Your BIOS is broken; bad RMRR [%#018Lx-%#018Lx]\n" > "BIOS vendor: %s; Ver: %s; Product Version: %s\n", >
Best regards, baolu
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