From ed51862f2f57cbce6fed2d4278cfe70a490899fd Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Mon, 17 Oct 2022 20:45:39 +0200 Subject: kvm: Add support for arch compat vm ioctls We will introduce the first architecture specific compat vm ioctl in the next patch. Add all necessary boilerplate to allow architectures to override compat vm ioctls when necessary. Signed-off-by: Alexander Graf Message-Id: <20221017184541.2658-2-graf@amazon.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index e30f1b4ecfa5..1376a47fedee 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4839,6 +4839,12 @@ struct compat_kvm_clear_dirty_log { }; }; +long __weak kvm_arch_vm_compat_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + return -ENOTTY; +} + static long kvm_vm_compat_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -4847,6 +4853,11 @@ static long kvm_vm_compat_ioctl(struct file *filp, if (kvm->mm != current->mm || kvm->vm_dead) return -EIO; + + r = kvm_arch_vm_compat_ioctl(filp, ioctl, arg); + if (r != -ENOTTY) + return r; + switch (ioctl) { #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT case KVM_CLEAR_DIRTY_LOG: { -- cgit v1.2.3 From 180418e2eb33be5c8d0b703c843e0ebc045aef80 Mon Sep 17 00:00:00 2001 From: Hou Wenlong Date: Mon, 17 Oct 2022 11:06:10 +0800 Subject: KVM: debugfs: Return retval of simple_attr_open() if it fails Although simple_attr_open() fails only with -ENOMEM with current code base, it would be nicer to return retval of simple_attr_open() directly in kvm_debugfs_open(). No functional change intended. Signed-off-by: Hou Wenlong Message-Id: <69d64d93accd1f33691b8a383ae555baee80f943.1665975828.git.houwenlong.hwl@antgroup.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1376a47fedee..f1df24c2bc84 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -5409,6 +5409,7 @@ static int kvm_debugfs_open(struct inode *inode, struct file *file, int (*get)(void *, u64 *), int (*set)(void *, u64), const char *fmt) { + int ret; struct kvm_stat_data *stat_data = (struct kvm_stat_data *) inode->i_private; @@ -5420,15 +5421,13 @@ static int kvm_debugfs_open(struct inode *inode, struct file *file, if (!kvm_get_kvm_safe(stat_data->kvm)) return -ENOENT; - if (simple_attr_open(inode, file, get, - kvm_stats_debugfs_mode(stat_data->desc) & 0222 - ? set : NULL, - fmt)) { + ret = simple_attr_open(inode, file, get, + kvm_stats_debugfs_mode(stat_data->desc) & 0222 + ? set : NULL, fmt); + if (ret) kvm_put_kvm(stat_data->kvm); - return -ENOMEM; - } - return 0; + return ret; } static int kvm_debugfs_release(struct inode *inode, struct file *file) -- cgit v1.2.3 From 7a2726ec3290c52f52ce8d5f5af73ab8c7681bc1 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Mon, 31 Oct 2022 08:36:15 +0800 Subject: KVM: Check KVM_CAP_DIRTY_LOG_{RING, RING_ACQ_REL} prior to enabling them There are two capabilities related to ring-based dirty page tracking: KVM_CAP_DIRTY_LOG_RING and KVM_CAP_DIRTY_LOG_RING_ACQ_REL. Both are supported by x86. However, arm64 supports KVM_CAP_DIRTY_LOG_RING_ACQ_REL only when the feature is supported on arm64. The userspace doesn't have to enable the advertised capability, meaning KVM_CAP_DIRTY_LOG_RING can be enabled on arm64 by userspace and it's wrong. Fix it by double checking if the capability has been advertised prior to enabling it. It's rejected to enable the capability if it hasn't been advertised. Fixes: 17601bfed909 ("KVM: Add KVM_CAP_DIRTY_LOG_RING_ACQ_REL capability and config option") Reported-by: Sean Christopherson Suggested-by: Sean Christopherson Signed-off-by: Gavin Shan Reviewed-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20221031003621.164306-4-gshan@redhat.com --- virt/kvm/kvm_main.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'virt/kvm/kvm_main.c') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1376a47fedee..46e8ed1ae647 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4585,6 +4585,9 @@ static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm, } case KVM_CAP_DIRTY_LOG_RING: case KVM_CAP_DIRTY_LOG_RING_ACQ_REL: + if (!kvm_vm_ioctl_check_extension_generic(kvm, cap->cap)) + return -EINVAL; + return kvm_vm_ioctl_enable_dirty_log_ring(kvm, cap->args[0]); default: return kvm_vm_ioctl_enable_cap(kvm, cap); -- cgit v1.2.3