From 978bff4e521dab0a72ee4f2627f9245f7d3d6f64 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Mon, 16 Dec 2019 15:19:24 +1100 Subject: [PATCH] powerpc/pseries/svm: Allow IOMMU to work in SVM H_PUT_TCE_INDIRECT uses a shared page to send up to 512 TCE to a hypervisor in a single hypercall. This does not work for secure VMs as the page needs to be shared or the VM should use H_PUT_TCE instead. This disables H_PUT_TCE_INDIRECT by clearing the FW_FEATURE_PUT_TCE_IND feature bit so SVMs will map TCEs using H_PUT_TCE. This is not a part of init_svm() as it is called too late after FW patching is done and may result in a warning like this: [ 3.727716] Firmware features changed after feature patching! [ 3.727965] WARNING: CPU: 0 PID: 1 at (...)arch/powerpc/lib/feature-fixups.c:466 check_features+0xa4/0xc0 Signed-off-by: Alexey Kardashevskiy Reviewed-by: Thiago Jung Bauermann Tested-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191216041924.42318-5-aik@ozlabs.ru --- arch/powerpc/platforms/pseries/firmware.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/powerpc/platforms/pseries/firmware.c b/arch/powerpc/platforms/pseries/firmware.c index d3acff23f2e3..3e49cc23a97a 100644 --- a/arch/powerpc/platforms/pseries/firmware.c +++ b/arch/powerpc/platforms/pseries/firmware.c @@ -22,6 +22,7 @@ #include #include #include +#include #include "pseries.h" @@ -101,6 +102,12 @@ static void __init fw_hypertas_feature_init(const char *hypertas, } } + if (is_secure_guest() && + (powerpc_firmware_features & FW_FEATURE_PUT_TCE_IND)) { + powerpc_firmware_features &= ~FW_FEATURE_PUT_TCE_IND; + pr_debug("SVM: disabling PUT_TCE_IND firmware feature\n"); + } + pr_debug(" <- fw_hypertas_feature_init()\n"); } -- 2.39.5