From: Thiago Jung Bauermann <bauerman@linux.ibm.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: Anshuman Khandual <anshuman.linux@gmail.com>,
Alexey Kardashevskiy <aik@ozlabs.ru>,
Mike Anderson <andmike@linux.ibm.com>,
Ram Pai <linuxram@us.ibm.com>,
linux-kernel@vger.kernel.org,
Claudio Carvalho <cclaudio@linux.ibm.com>,
Ryan Grimm <grimm@linux.vnet.ibm.com>,
Paul Mackerras <paulus@samba.org>, Christoph Hellwig <hch@lst.de>,
Thiago Jung Bauermann <bauerman@linux.ibm.com>
Subject: [PATCH v3 11/16] powerpc/pseries/svm: Export guest SVM status to user space via sysfs
Date: Tue, 6 Aug 2019 02:22:32 -0300 [thread overview]
Message-ID: <20190806052237.12525-12-bauerman@linux.ibm.com> (raw)
In-Reply-To: <20190806052237.12525-1-bauerman@linux.ibm.com>
From: Ryan Grimm <grimm@linux.vnet.ibm.com>
User space might want to know it's running in a secure VM. It can't do
a mfmsr because mfmsr is a privileged instruction.
The solution here is to create a cpu attribute:
/sys/devices/system/cpu/svm
which will read 0 or 1 based on the S bit of the guest's CPU 0.
Signed-off-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Reviewed-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
---
arch/powerpc/kernel/sysfs.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)
diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c
index e2147d7c9e72..f7100ab77d29 100644
--- a/arch/powerpc/kernel/sysfs.c
+++ b/arch/powerpc/kernel/sysfs.c
@@ -19,6 +19,7 @@
#include <asm/smp.h>
#include <asm/pmc.h>
#include <asm/firmware.h>
+#include <asm/svm.h>
#include "cacheinfo.h"
#include "setup.h"
@@ -715,6 +716,32 @@ static struct device_attribute pa6t_attrs[] = {
#endif /* HAS_PPC_PMC_PA6T */
#endif /* HAS_PPC_PMC_CLASSIC */
+#ifdef CONFIG_PPC_SVM
+static void get_svm(void *val)
+{
+ u32 *value = val;
+
+ *value = is_secure_guest();
+}
+
+static ssize_t show_svm(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ u32 val;
+ smp_call_function_single(0, get_svm, &val, 1);
+ return sprintf(buf, "%u\n", val);
+}
+static DEVICE_ATTR(svm, 0444, show_svm, NULL);
+
+static void create_svm_file(void)
+{
+ device_create_file(cpu_subsys.dev_root, &dev_attr_svm);
+}
+#else
+static void create_svm_file(void)
+{
+}
+#endif /* CONFIG_PPC_SVM */
+
static int register_cpu_online(unsigned int cpu)
{
struct cpu *c = &per_cpu(cpu_devices, cpu);
@@ -1058,6 +1085,8 @@ static int __init topology_init(void)
sysfs_create_dscr_default();
#endif /* CONFIG_PPC64 */
+ create_svm_file();
+
return 0;
}
subsys_initcall(topology_init);
next prev parent reply other threads:[~2019-08-06 5:49 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-06 5:22 [PATCH v3 00/16] Secure Virtual Machine Enablement Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 01/16] powerpc/kernel: Add ucall_norets() ultravisor call handler Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 02/16] powerpc/pseries: Introduce option to build secure virtual machines Thiago Jung Bauermann
2019-08-06 5:22 ` [RFC PATCH v3 03/16] powerpc: Add support for adding an ESM blob to the zImage wrapper Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 04/16] powerpc/prom_init: Add the ESM call to prom_init Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 05/16] powerpc/pseries/svm: Add helpers for UV_SHARE_PAGE and UV_UNSHARE_PAGE Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 06/16] powerpc: Introduce the MSR_S bit Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 07/16] powerpc/pseries: Add and use LPPACA_SIZE constant Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 08/16] powerpc/pseries/svm: Use shared memory for LPPACA structures Thiago Jung Bauermann
2019-08-12 12:36 ` Michael Ellerman
2019-08-12 21:43 ` Thiago Jung Bauermann
2019-08-14 10:54 ` Michael Ellerman
2019-08-16 0:52 ` Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 09/16] powerpc/pseries/svm: Use shared memory for Debug Trace Log (DTL) Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 10/16] powerpc/pseries/svm: Unshare all pages before kexecing a new kernel Thiago Jung Bauermann
2019-08-06 5:22 ` Thiago Jung Bauermann [this message]
2019-08-12 13:03 ` [PATCH v3 11/16] powerpc/pseries/svm: Export guest SVM status to user space via sysfs Michael Ellerman
2019-08-12 23:21 ` Thiago Jung Bauermann
2019-08-15 6:30 ` Michael Ellerman
2019-08-16 0:49 ` Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 12/16] powerpc/pseries/svm: Disable doorbells in SVM guests Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 13/16] powerpc/pseries/iommu: Don't use dma_iommu_ops on secure guests Thiago Jung Bauermann
2019-08-06 5:48 ` Christoph Hellwig
2019-08-07 1:37 ` Thiago Jung Bauermann
2019-08-06 5:22 ` [PATCH v3 14/16] powerpc/pseries/svm: Force SWIOTLB for " Thiago Jung Bauermann
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