From 361ae8cb57ec35ace2fa5f9695dba14eca9893e0 Mon Sep 17 00:00:00 2001 From: Nicolas Kaiser Date: Wed, 30 Mar 2011 21:14:26 +0200 Subject: [PATCH 1/4] xen: events: fix error checks in bind_*_to_irqhandler() Checking 'irq < 0' doesn't work when 'irq' is unsigned. The assigned bind_evtchn_to_irq() and bind_virq_to_irq() return int, so using int appears appropriate. Signed-off-by: Nicolas Kaiser Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/events.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/xen/events.c b/drivers/xen/events.c index 036343ba204e..589f0a53a604 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -912,8 +912,7 @@ int bind_evtchn_to_irqhandler(unsigned int evtchn, unsigned long irqflags, const char *devname, void *dev_id) { - unsigned int irq; - int retval; + int irq, retval; irq = bind_evtchn_to_irq(evtchn); if (irq < 0) @@ -955,8 +954,7 @@ int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, irq_handler_t handler, unsigned long irqflags, const char *devname, void *dev_id) { - unsigned int irq; - int retval; + int irq, retval; irq = bind_virq_to_irq(virq, cpu); if (irq < 0) From d88885d0923ae27b01dfcec644f94829b1e46bea Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Mon, 4 Apr 2011 14:48:20 -0400 Subject: [PATCH 2/4] xen/debug: Don't be so verbose with WARN on 1-1 mapping errors. There are valid situations in which this error is not a warning. Mainly when QEMU maps a guest memory and uses the VM_IO flag to set the MFNs. For right now make the WARN be WARN_ONCE. In the future we will: 1). Remove the VM_IO code handling.. 2). .. which will also remove this debug facility. Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index c82df6c9c0f0..a991b57f91fe 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -565,13 +565,13 @@ pte_t xen_make_pte_debug(pteval_t pte) if (io_page && (xen_initial_domain() || addr >= ISA_END_ADDRESS)) { other_addr = pfn_to_mfn(addr >> PAGE_SHIFT) << PAGE_SHIFT; - WARN(addr != other_addr, + WARN_ONCE(addr != other_addr, "0x%lx is using VM_IO, but it is 0x%lx!\n", (unsigned long)addr, (unsigned long)other_addr); } else { pteval_t iomap_set = (_pte.pte & PTE_FLAGS_MASK) & _PAGE_IOMAP; other_addr = (_pte.pte & PTE_PFN_MASK); - WARN((addr == other_addr) && (!io_page) && (!iomap_set), + WARN_ONCE((addr == other_addr) && (!io_page) && (!iomap_set), "0x%lx is missing VM_IO (and wasn't fixed)!\n", (unsigned long)addr); } From 61f4237d5b005767a76f4f3694e68e6f78f392d9 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Sat, 18 Sep 2010 22:25:30 -0700 Subject: [PATCH 3/4] xen: just completely disable XSAVE Some (old) versions of Xen just kill the domain if it tries to set any unknown bits in CR4, so we can't reliably probe for OSXSAVE in CR4. Since Xen doesn't support XSAVE for guests at the moment, and no such support is being worked on, there's no downside in just unconditionally masking XSAVE support. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/enlighten.c | 18 +----------------- 1 file changed, 1 insertion(+), 17 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 49dbd78ec3cb..66272a237622 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -250,23 +250,7 @@ static __init void xen_init_cpuid_mask(void) ~((1 << X86_FEATURE_APIC) | /* disable local APIC */ (1 << X86_FEATURE_ACPI)); /* disable ACPI */ - ax = 1; - cx = 0; - xen_cpuid(&ax, &bx, &cx, &dx); - - /* cpuid claims we support xsave; try enabling it to see what happens */ - if (cx & (1 << (X86_FEATURE_XSAVE % 32))) { - unsigned long cr4; - - set_in_cr4(X86_CR4_OSXSAVE); - - cr4 = read_cr4(); - - if ((cr4 & X86_CR4_OSXSAVE) == 0) - cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32)); - - clear_in_cr4(X86_CR4_OSXSAVE); - } + cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32)); /* disable XSAVE */ } static void xen_set_debugreg(int reg, unsigned long val) From 947ccf9c3c30307b774af3666ee74fcd9f47f646 Mon Sep 17 00:00:00 2001 From: Shan Haitao Date: Tue, 9 Nov 2010 11:43:36 -0800 Subject: [PATCH 4/4] xen: Allow PV-OPS kernel to detect whether XSAVE is supported Xen fails to mask XSAVE from the cpuid feature, despite not historically supporting guest use of XSAVE. However, now that XSAVE support has been added to Xen, we need to reliably detect its presence. The most reliable way to do this is to look at the OSXSAVE feature in cpuid which is set iff the OS (Xen, in this case), has set CR4.OSXSAVE. [ Cleaned up conditional a bit. - Jeremy ] Signed-off-by: Shan Haitao Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Konrad Rzeszutek Wilk --- arch/x86/xen/enlighten.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 66272a237622..e3c6a06cf725 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -238,6 +238,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, static __init void xen_init_cpuid_mask(void) { unsigned int ax, bx, cx, dx; + unsigned int xsave_mask; cpuid_leaf1_edx_mask = ~((1 << X86_FEATURE_MCE) | /* disable MCE */ @@ -249,8 +250,16 @@ static __init void xen_init_cpuid_mask(void) cpuid_leaf1_edx_mask &= ~((1 << X86_FEATURE_APIC) | /* disable local APIC */ (1 << X86_FEATURE_ACPI)); /* disable ACPI */ + ax = 1; + xen_cpuid(&ax, &bx, &cx, &dx); - cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32)); /* disable XSAVE */ + xsave_mask = + (1 << (X86_FEATURE_XSAVE % 32)) | + (1 << (X86_FEATURE_OSXSAVE % 32)); + + /* Xen will set CR4.OSXSAVE if supported and not disabled by force */ + if ((cx & xsave_mask) != xsave_mask) + cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */ } static void xen_set_debugreg(int reg, unsigned long val)