From d780a31271b2f455cb4b83eb018ecfb1c28ef5c1 Mon Sep 17 00:00:00 2001 From: Tim Gardner Date: Tue, 29 Oct 2013 09:13:54 -0600 Subject: [PATCH 1/2] KVM: Fix modprobe failure for kvm_intel/kvm_amd The x86 specific kvm init creates a new conflicting debugfs directory which causes modprobe issues with kvm_intel and kvm_amd. For example, sudo modprobe kvm_amd modprobe: ERROR: could not insert 'kvm_amd': Bad address The simplest fix is to just rename the directory. The following KVM config options are set: CONFIG_KVM_GUEST=y CONFIG_KVM_DEBUG_FS=y CONFIG_HAVE_KVM=y CONFIG_HAVE_KVM_IRQCHIP=y CONFIG_HAVE_KVM_IRQ_ROUTING=y CONFIG_HAVE_KVM_EVENTFD=y CONFIG_KVM_APIC_ARCHITECTURE=y CONFIG_KVM_MMIO=y CONFIG_KVM_ASYNC_PF=y CONFIG_HAVE_KVM_MSI=y CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT=y CONFIG_KVM=m CONFIG_KVM_INTEL=m CONFIG_KVM_AMD=m CONFIG_KVM_DEVICE_ASSIGNMENT=y Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Gleb Natapov Cc: Raghavendra K T Cc: Marcelo Tosatti Signed-off-by: Tim Gardner [Change debugfs directory name. - Paolo] Signed-off-by: Paolo Bonzini --- arch/x86/kernel/kvm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index a0e2a8a80c94..b2046e4d0b59 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -609,7 +609,7 @@ static struct dentry *d_kvm_debug; struct dentry *kvm_init_debugfs(void) { - d_kvm_debug = debugfs_create_dir("kvm", NULL); + d_kvm_debug = debugfs_create_dir("kvm-guest", NULL); if (!d_kvm_debug) printk(KERN_WARNING "Could not create 'kvm' debugfs directory\n"); From 0c8eb04a6241da28deb108181213b791c378123b Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 30 Oct 2013 12:12:13 +0100 Subject: [PATCH 2/2] KVM: use a more sensible error number when debugfs directory creation fails I don't know if this was due to cut and paste, or somebody was really using a D20 to pick the error code for kvm_init_debugfs as suggested by Linus (EFAULT is 14, so the possibility cannot be entirely ruled out). In any case, this patch fixes it. Reported-by: Tim Gardner Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a9dd682cf5e3..1cf9ccb01013 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3091,7 +3091,7 @@ static const struct file_operations *stat_fops[] = { static int kvm_init_debug(void) { - int r = -EFAULT; + int r = -EEXIST; struct kvm_stats_debugfs_item *p; kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);