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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-12 15:20:28 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-12 15:20:28 +0200 |
commit | ccff9b1db693062b0a9c9070f4304deb47ef215c (patch) | |
tree | a956cc800a03f11254105fbd9926bab537b6863f | |
parent | Merge branch 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/p... (diff) | |
parent | xen/pv-on-hvm kexec: add quirk for Xen 3.4 and shutdown watches. (diff) | |
download | linux-ccff9b1db693062b0a9c9070f4304deb47ef215c.tar.xz linux-ccff9b1db693062b0a9c9070f4304deb47ef215c.zip |
Merge tag 'stable/for-linus-3.7-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen fixes from Konrad Rzeszutek Wilk:
"This has four bug-fixes and one tiny feature that I forgot to put
initially in my tree due to oversight.
The feature is for kdump kernels to speed up the /proc/vmcore reading.
There is a ram_is_pfn helper function that the different platforms can
register for. We are now doing that.
The bug-fixes cover some embarrassing struct pv_cpu_ops variables
being set to NULL on Xen (but not baremetal). We had a similar issue
in the past with {write|read}_msr_safe and this fills the three
missing ones. The other bug-fix is to make the console output (hvc)
be capable of dealing with misbehaving backends and not fall flat on
its face. Lastly, a quirk for older XenBus implementations that came
with an ancient v3.4 hypervisor (so RHEL5 based) - reading of certain
non-existent attributes just hangs the guest during bootup - so we
take precaution of not doing that on such older installations.
Feature:
- Register a pfn_is_ram helper to speed up reading of /proc/vmcore.
Bug-fixes:
- Three pvops call for Xen were undefined causing BUG_ONs.
- Add a quirk so that the shutdown watches (used by kdump) are not
used with older Xen (3.4).
- Fix ungraceful state transition for the HVC console."
* tag 'stable/for-linus-3.7-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pv-on-hvm kexec: add quirk for Xen 3.4 and shutdown watches.
xen/bootup: allow {read|write}_cr8 pvops call.
xen/bootup: allow read_tscp call for Xen PV guests.
xen pv-on-hvm: add pfn_is_ram helper for kdump
xen/hvc: handle backend CLOSED without CLOSING
-rw-r--r-- | arch/x86/xen/enlighten.c | 18 | ||||
-rw-r--r-- | arch/x86/xen/mmu.c | 41 | ||||
-rw-r--r-- | drivers/tty/hvc/hvc_xen.c | 5 | ||||
-rw-r--r-- | drivers/xen/xenbus/xenbus_xs.c | 21 | ||||
-rw-r--r-- | include/xen/interface/hvm/hvm_op.h | 19 |
5 files changed, 102 insertions, 2 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index bf788d34530d..e3497f240eab 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -987,7 +987,16 @@ static void xen_write_cr4(unsigned long cr4) native_write_cr4(cr4); } - +#ifdef CONFIG_X86_64 +static inline unsigned long xen_read_cr8(void) +{ + return 0; +} +static inline void xen_write_cr8(unsigned long val) +{ + BUG_ON(val); +} +#endif static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high) { int ret; @@ -1156,6 +1165,11 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = { .read_cr4_safe = native_read_cr4_safe, .write_cr4 = xen_write_cr4, +#ifdef CONFIG_X86_64 + .read_cr8 = xen_read_cr8, + .write_cr8 = xen_write_cr8, +#endif + .wbinvd = native_wbinvd, .read_msr = native_read_msr_safe, @@ -1164,6 +1178,8 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = { .read_tsc = native_read_tsc, .read_pmc = native_read_pmc, + .read_tscp = native_read_tscp, + .iret = xen_iret, .irq_enable_sysexit = xen_sysexit, #ifdef CONFIG_X86_64 diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index fd28d86fe3d2..6226c99729b9 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -47,6 +47,7 @@ #include <linux/gfp.h> #include <linux/memblock.h> #include <linux/seq_file.h> +#include <linux/crash_dump.h> #include <trace/events/xen.h> @@ -2381,6 +2382,43 @@ void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region); #ifdef CONFIG_XEN_PVHVM +#ifdef CONFIG_PROC_VMCORE +/* + * This function is used in two contexts: + * - the kdump kernel has to check whether a pfn of the crashed kernel + * was a ballooned page. vmcore is using this function to decide + * whether to access a pfn of the crashed kernel. + * - the kexec kernel has to check whether a pfn was ballooned by the + * previous kernel. If the pfn is ballooned, handle it properly. + * Returns 0 if the pfn is not backed by a RAM page, the caller may + * handle the pfn special in this case. + */ +static int xen_oldmem_pfn_is_ram(unsigned long pfn) +{ + struct xen_hvm_get_mem_type a = { + .domid = DOMID_SELF, + .pfn = pfn, + }; + int ram; + + if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a)) + return -ENXIO; + + switch (a.mem_type) { + case HVMMEM_mmio_dm: + ram = 0; + break; + case HVMMEM_ram_rw: + case HVMMEM_ram_ro: + default: + ram = 1; + break; + } + + return ram; +} +#endif + static void xen_hvm_exit_mmap(struct mm_struct *mm) { struct xen_hvm_pagetable_dying a; @@ -2411,6 +2449,9 @@ void __init xen_hvm_init_mmu_ops(void) { if (is_pagetable_dying_supported()) pv_mmu_ops.exit_mmap = xen_hvm_exit_mmap; +#ifdef CONFIG_PROC_VMCORE + register_oldmem_pfn_is_ram(&xen_oldmem_pfn_is_ram); +#endif } #endif diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c index 2944ff88fdc0..f4abfe238f98 100644 --- a/drivers/tty/hvc/hvc_xen.c +++ b/drivers/tty/hvc/hvc_xen.c @@ -478,7 +478,6 @@ static void xencons_backend_changed(struct xenbus_device *dev, case XenbusStateInitialising: case XenbusStateInitialised: case XenbusStateUnknown: - case XenbusStateClosed: break; case XenbusStateInitWait: @@ -488,6 +487,10 @@ static void xencons_backend_changed(struct xenbus_device *dev, xenbus_switch_state(dev, XenbusStateConnected); break; + case XenbusStateClosed: + if (dev->state == XenbusStateClosed) + break; + /* Missed the backend's CLOSING state -- fallthrough */ case XenbusStateClosing: xenbus_frontend_closed(dev); break; diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c index 131dec04794e..48220e129f85 100644 --- a/drivers/xen/xenbus/xenbus_xs.c +++ b/drivers/xen/xenbus/xenbus_xs.c @@ -48,6 +48,7 @@ #include <xen/xenbus.h> #include <xen/xen.h> #include "xenbus_comms.h" +#include <asm/xen/hypervisor.h> struct xs_stored_msg { struct list_head list; @@ -618,7 +619,24 @@ static struct xenbus_watch *find_watch(const char *token) return NULL; } +/* + * Certain older XenBus toolstack cannot handle reading values that are + * not populated. Some Xen 3.4 installation are incapable of doing this + * so if we are running on anything older than 4 do not attempt to read + * control/platform-feature-xs_reset_watches. + */ +static bool xen_strict_xenbus_quirk() +{ + uint32_t eax, ebx, ecx, edx, base; + + base = xen_cpuid_base(); + cpuid(base + 1, &eax, &ebx, &ecx, &edx); + if ((eax >> 16) < 4) + return true; + return false; + +} static void xs_reset_watches(void) { int err, supported = 0; @@ -626,6 +644,9 @@ static void xs_reset_watches(void) if (!xen_hvm_domain() || xen_initial_domain()) return; + if (xen_strict_xenbus_quirk()) + return; + err = xenbus_scanf(XBT_NIL, "control", "platform-feature-xs_reset_watches", "%d", &supported); if (err != 1 || !supported) diff --git a/include/xen/interface/hvm/hvm_op.h b/include/xen/interface/hvm/hvm_op.h index a4827f46ee97..956a04682865 100644 --- a/include/xen/interface/hvm/hvm_op.h +++ b/include/xen/interface/hvm/hvm_op.h @@ -43,4 +43,23 @@ struct xen_hvm_pagetable_dying { typedef struct xen_hvm_pagetable_dying xen_hvm_pagetable_dying_t; DEFINE_GUEST_HANDLE_STRUCT(xen_hvm_pagetable_dying_t); +enum hvmmem_type_t { + HVMMEM_ram_rw, /* Normal read/write guest RAM */ + HVMMEM_ram_ro, /* Read-only; writes are discarded */ + HVMMEM_mmio_dm, /* Reads and write go to the device model */ +}; + +#define HVMOP_get_mem_type 15 +/* Return hvmmem_type_t for the specified pfn. */ +struct xen_hvm_get_mem_type { + /* Domain to be queried. */ + domid_t domid; + /* OUT variable. */ + uint16_t mem_type; + uint16_t pad[2]; /* align next field on 8-byte boundary */ + /* IN variable. */ + uint64_t pfn; +}; +DEFINE_GUEST_HANDLE_STRUCT(xen_hvm_get_mem_type); + #endif /* __XEN_PUBLIC_HVM_HVM_OP_H__ */ |