linux-kselftest.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ben Gardon <bgardon@google.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	linux-kselftest@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	Cannon Matthews <cannonmatthews@google.com>,
	Peter Xu <peterx@redhat.com>, Andrew Jones <drjones@redhat.com>,
	Peter Shier <pshier@google.com>, Oliver Upton <oupton@google.com>,
	Ben Gardon <bgardon@google.com>
Subject: [PATCH v4 09/10] KVM: selftests: Stop memslot creation in KVM internal memslot region
Date: Thu, 23 Jan 2020 10:04:35 -0800	[thread overview]
Message-ID: <20200123180436.99487-10-bgardon@google.com> (raw)
In-Reply-To: <20200123180436.99487-1-bgardon@google.com>

KVM creates internal memslots covering the region between 3G and 4G in
the guest physical address space, when the first vCPU is created.
Mapping this region before creation of the first vCPU causes vCPU
creation to fail. Prohibit tests from creating such a memslot and fail
with a helpful warning when they try to.

Signed-off-by: Ben Gardon <bgardon@google.com>
---
 tools/testing/selftests/kvm/lib/kvm_util.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 41cf45416060f..5b971c04f1643 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -113,6 +113,8 @@ const char * const vm_guest_mode_string[] = {
 _Static_assert(sizeof(vm_guest_mode_string)/sizeof(char *) == NUM_VM_MODES,
 	       "Missing new mode strings?");
 
+#define KVM_INTERNAL_MEMSLOTS_START_PADDR (3UL << 30)
+#define KVM_INTERNAL_MEMSLOTS_END_PADDR (4UL << 30)
 /*
  * VM Create
  *
@@ -593,6 +595,20 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
 		"  vm->max_gfn: 0x%lx vm->page_size: 0x%x",
 		guest_paddr, npages, vm->max_gfn, vm->page_size);
 
+	/*
+	 * Check that this region does not overlap with KVM internal memslots
+	 * which are created when the first vCPU is created.
+	 */
+	TEST_ASSERT(guest_paddr >= KVM_INTERNAL_MEMSLOTS_END_PADDR ||
+		    guest_paddr + npages < KVM_INTERNAL_MEMSLOTS_START_PADDR,
+		    "Memslot overlapps with region mapped by internal KVM\n"
+		    "memslots:\n"
+		    "  Requested paddr range:      [0x%lx, 0x%lx)\n"
+		    "  KVM internal memslot range: [0x%lx, 0x%lx)\n",
+		    guest_paddr, guest_paddr + npages,
+		    KVM_INTERNAL_MEMSLOTS_START_PADDR,
+		    KVM_INTERNAL_MEMSLOTS_END_PADDR);
+
 	/*
 	 * Confirm a mem region with an overlapping address doesn't
 	 * already exist.
-- 
2.25.0.341.g760bfbb309-goog


  parent reply	other threads:[~2020-01-23 18:05 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-23 18:04 [PATCH v4 00/10] Create a userfaultfd demand paging test Ben Gardon
2020-01-23 18:04 ` [PATCH v4 01/10] KVM: selftests: Create a " Ben Gardon
2020-01-24  9:49   ` Andrew Jones
2020-01-27  9:18   ` Thomas Huth
2020-01-23 18:04 ` [PATCH v4 02/10] KVM: selftests: Add demand paging content to the " Ben Gardon
2020-01-23 18:04 ` [PATCH v4 03/10] KVM: selftests: Add configurable demand paging delay Ben Gardon
2020-01-23 18:04 ` [PATCH v4 04/10] KVM: selftests: Add memory size parameter to the demand paging test Ben Gardon
2020-01-24 10:01   ` Andrew Jones
2020-01-23 18:04 ` [PATCH v4 05/10] KVM: selftests: Pass args to vCPU in global vCPU args struct Ben Gardon
2020-01-23 18:04 ` [PATCH v4 06/10] KVM: selftests: Add support for vcpu_args_set to aarch64 and s390x Ben Gardon
2020-01-24  9:03   ` Paolo Bonzini
2020-01-24  9:35     ` Andrew Jones
2020-01-24  9:44       ` Paolo Bonzini
2020-01-24 10:45       ` Andrew Jones
2020-01-24 18:33     ` Christian Borntraeger
2020-01-25  9:34   ` Paolo Bonzini
2020-01-27  8:38     ` Andrew Jones
2020-01-27  9:01   ` Thomas Huth
2020-01-23 18:04 ` [PATCH v4 07/10] KVM: selftests: Support multiple vCPUs in demand paging test Ben Gardon
2020-01-24 10:16   ` Andrew Jones
2020-01-24 10:49   ` Andrew Jones
2020-01-25  9:39     ` Paolo Bonzini
2020-01-27  8:39       ` Andrew Jones
2020-01-23 18:04 ` [PATCH v4 08/10] KVM: selftests: Time guest demand paging Ben Gardon
2020-01-24 10:21   ` Andrew Jones
2020-01-23 18:04 ` Ben Gardon [this message]
2020-01-24  8:58   ` [PATCH v4 09/10] KVM: selftests: Stop memslot creation in KVM internal memslot region Paolo Bonzini
2020-01-24 18:41     ` Ben Gardon
2020-01-25  9:37       ` Paolo Bonzini
2020-01-27 17:28         ` Ben Gardon
2020-01-23 18:04 ` [PATCH v4 10/10] KVM: selftests: Move memslot 0 above KVM internal memslots Ben Gardon
2020-01-24  9:01   ` Paolo Bonzini
2020-01-24 18:53     ` Ben Gardon
2020-01-27  9:42   ` Thomas Huth
2020-01-24  9:03 ` [PATCH v4 00/10] Create a userfaultfd demand paging test Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200123180436.99487-10-bgardon@google.com \
    --to=bgardon@google.com \
    --cc=cannonmatthews@google.com \
    --cc=drjones@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=oupton@google.com \
    --cc=pbonzini@redhat.com \
    --cc=peterx@redhat.com \
    --cc=pshier@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).