Hi Paul, Julien
On 26.09.19 14:24, Julien Grall wrote:
Hi Paul,
On 9/26/19 11:03 AM, Paul Durrant wrote:
...when the IOMMU is not enabled.
80ff3d338dc9 "iommu: tidy up iommu_use_hap_pt() and need_iommu_pt_sync()
macros" introduced CONFIG_IOMMU_FORCE_PT_SHARE, which causes the global
'iommu_hap_pt_share' option to be replaced with a #define-d value of
true.
In this configuration, calling clear_iommu_hap_pt_share() will result
trigger the aforementioned ASSERT.
CONFIG_IOMMU_FORCE_PT_SHARE is always selected for ARM builds and,
because clear_iommu_hap_pt_share() is called by the common iommu_setup()
function if the IOMMU is not enabled, it is no longer safe to disable
the
IOMMU on ARM systems.
However, running with the IOMMU disabled is a valid configuration for
ARM
systems, so this patch rectifies the problem by removing the call to
clear_iommu_hap_pt_share() from common code. As a side effect of this,
however, it becomes possible on x86 systems for iommu_enabled to be
false
but iommu_hap_pt_share to be true. Thus the code in sysctl.c
needs to be changed to make sure that
XEN_SYSCTL_PHYSCAP_iommu_hap_pt_share
is not erroneously advertised when the IOMMU has been disabled.
Signed-off-by: Paul Durrant <paul.durr...@citrix.com>
Reported-by: Oleksandr <olekst...@gmail.com>
With one NIT below:
Acked-by: Julien Grall <julien.gr...@arm.com>
Could you, please, change to:
Reported-by: Oleksandr Tyshchenko <oleksandr_tyshche...@epam.com>
You can also add if really needed:
[with IOMMU disabled on Arm]
Tested-by: Oleksandr Tyshchenko <oleksandr_tyshche...@epam.com>
--
Regards,
Oleksandr Tyshchenko
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