From 4bf2cc9645599382e34b7d0cbe5a13d0de98194e Mon Sep 17 00:00:00 2001 From: Souptick Joarder Date: Sun, 15 Apr 2018 00:45:42 +0530 Subject: [PATCH 1/6] xen: Change return type to vm_fault_t Use new return type vm_fault_t for fault handler in struct vm_operations_struct. Signed-off-by: Souptick Joarder Reviewed-by: Matthew Wilcox Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross --- drivers/xen/privcmd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index 1c909183c42a..0a778d30d333 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -801,7 +801,7 @@ static void privcmd_close(struct vm_area_struct *vma) kfree(pages); } -static int privcmd_fault(struct vm_fault *vmf) +static vm_fault_t privcmd_fault(struct vm_fault *vmf) { printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n", vmf->vma, vmf->vma->vm_start, vmf->vma->vm_end, From 3ad0876554cafa368f574d4d408468510543e9ff Mon Sep 17 00:00:00 2001 From: Paul Durrant Date: Wed, 9 May 2018 14:16:12 +0100 Subject: [PATCH 2/6] xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE My recent Xen patch series introduces a new HYPERVISOR_memory_op to support direct priv-mapping of certain guest resources (such as ioreq pages, used by emulators) by a tools domain, rather than having to access such resources via the guest P2M. This patch adds the necessary infrastructure to the privcmd driver and Xen MMU code to support direct resource mapping. NOTE: The adjustment in the MMU code is partially cosmetic. Xen will now allow a PV tools domain to map guest pages either by GFN or MFN, thus the term 'mfn' has been swapped for 'pfn' in the lower layers of the remap code. Signed-off-by: Paul Durrant Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross --- arch/arm/xen/enlighten.c | 11 +++ arch/x86/xen/mmu.c | 60 ++++++++++----- drivers/xen/privcmd.c | 133 +++++++++++++++++++++++++++++++++ include/uapi/xen/privcmd.h | 11 +++ include/xen/interface/memory.h | 66 ++++++++++++++++ include/xen/interface/xen.h | 7 +- include/xen/xen-ops.h | 24 +++++- 7 files changed, 291 insertions(+), 21 deletions(-) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index ba7f4c8f5c3e..8073625371f5 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -89,6 +89,17 @@ int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, } EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); +/* Not used by XENFEAT_auto_translated guests. */ +int xen_remap_domain_mfn_array(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *mfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, struct page **pages) +{ + return -ENOSYS; +} +EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array); + static void xen_read_wallclock(struct timespec64 *ts) { u32 version; diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index d33e7dbe3129..af2960cb7a3e 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -65,37 +65,44 @@ static void xen_flush_tlb_all(void) #define REMAP_BATCH_SIZE 16 struct remap_data { - xen_pfn_t *mfn; + xen_pfn_t *pfn; bool contiguous; + bool no_translate; pgprot_t prot; struct mmu_update *mmu_update; }; -static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token, +static int remap_area_pfn_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr, void *data) { struct remap_data *rmd = data; - pte_t pte = pte_mkspecial(mfn_pte(*rmd->mfn, rmd->prot)); + pte_t pte = pte_mkspecial(mfn_pte(*rmd->pfn, rmd->prot)); - /* If we have a contiguous range, just update the mfn itself, - else update pointer to be "next mfn". */ + /* + * If we have a contiguous range, just update the pfn itself, + * else update pointer to be "next pfn". + */ if (rmd->contiguous) - (*rmd->mfn)++; + (*rmd->pfn)++; else - rmd->mfn++; + rmd->pfn++; - rmd->mmu_update->ptr = virt_to_machine(ptep).maddr | MMU_NORMAL_PT_UPDATE; + rmd->mmu_update->ptr = virt_to_machine(ptep).maddr; + rmd->mmu_update->ptr |= rmd->no_translate ? + MMU_PT_UPDATE_NO_TRANSLATE : + MMU_NORMAL_PT_UPDATE; rmd->mmu_update->val = pte_val_ma(pte); rmd->mmu_update++; return 0; } -static int do_remap_gfn(struct vm_area_struct *vma, +static int do_remap_pfn(struct vm_area_struct *vma, unsigned long addr, - xen_pfn_t *gfn, int nr, + xen_pfn_t *pfn, int nr, int *err_ptr, pgprot_t prot, - unsigned domid, + unsigned int domid, + bool no_translate, struct page **pages) { int err = 0; @@ -106,11 +113,14 @@ static int do_remap_gfn(struct vm_area_struct *vma, BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); - rmd.mfn = gfn; + rmd.pfn = pfn; rmd.prot = prot; - /* We use the err_ptr to indicate if there we are doing a contiguous - * mapping or a discontigious mapping. */ + /* + * We use the err_ptr to indicate if there we are doing a contiguous + * mapping or a discontigious mapping. + */ rmd.contiguous = !err_ptr; + rmd.no_translate = no_translate; while (nr) { int index = 0; @@ -121,7 +131,7 @@ static int do_remap_gfn(struct vm_area_struct *vma, rmd.mmu_update = mmu_update; err = apply_to_page_range(vma->vm_mm, addr, range, - remap_area_mfn_pte_fn, &rmd); + remap_area_pfn_pte_fn, &rmd); if (err) goto out; @@ -175,7 +185,8 @@ int xen_remap_domain_gfn_range(struct vm_area_struct *vma, if (xen_feature(XENFEAT_auto_translated_physmap)) return -EOPNOTSUPP; - return do_remap_gfn(vma, addr, &gfn, nr, NULL, prot, domid, pages); + return do_remap_pfn(vma, addr, &gfn, nr, NULL, prot, domid, false, + pages); } EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range); @@ -194,10 +205,25 @@ int xen_remap_domain_gfn_array(struct vm_area_struct *vma, * cause of "wrong memory was mapped in". */ BUG_ON(err_ptr == NULL); - return do_remap_gfn(vma, addr, gfn, nr, err_ptr, prot, domid, pages); + return do_remap_pfn(vma, addr, gfn, nr, err_ptr, prot, domid, + false, pages); } EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array); +int xen_remap_domain_mfn_array(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *mfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, struct page **pages) +{ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return -EOPNOTSUPP; + + return do_remap_pfn(vma, addr, mfn, nr, err_ptr, prot, domid, + true, pages); +} +EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array); + /* Returns: 0 success */ int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, int nr, struct page **pages) diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index 0a778d30d333..8ae0349d9f0a 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -722,6 +723,134 @@ static long privcmd_ioctl_restrict(struct file *file, void __user *udata) return 0; } +struct remap_pfn { + struct mm_struct *mm; + struct page **pages; + pgprot_t prot; + unsigned long i; +}; + +static int remap_pfn_fn(pte_t *ptep, pgtable_t token, unsigned long addr, + void *data) +{ + struct remap_pfn *r = data; + struct page *page = r->pages[r->i]; + pte_t pte = pte_mkspecial(pfn_pte(page_to_pfn(page), r->prot)); + + set_pte_at(r->mm, addr, ptep, pte); + r->i++; + + return 0; +} + +static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata) +{ + struct privcmd_data *data = file->private_data; + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + struct privcmd_mmap_resource kdata; + xen_pfn_t *pfns = NULL; + struct xen_mem_acquire_resource xdata; + int rc; + + if (copy_from_user(&kdata, udata, sizeof(kdata))) + return -EFAULT; + + /* If restriction is in place, check the domid matches */ + if (data->domid != DOMID_INVALID && data->domid != kdata.dom) + return -EPERM; + + down_write(&mm->mmap_sem); + + vma = find_vma(mm, kdata.addr); + if (!vma || vma->vm_ops != &privcmd_vm_ops) { + rc = -EINVAL; + goto out; + } + + pfns = kcalloc(kdata.num, sizeof(*pfns), GFP_KERNEL); + if (!pfns) { + rc = -ENOMEM; + goto out; + } + + if (xen_feature(XENFEAT_auto_translated_physmap)) { + unsigned int nr = DIV_ROUND_UP(kdata.num, XEN_PFN_PER_PAGE); + struct page **pages; + unsigned int i; + + rc = alloc_empty_pages(vma, nr); + if (rc < 0) + goto out; + + pages = vma->vm_private_data; + for (i = 0; i < kdata.num; i++) { + xen_pfn_t pfn = + page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]); + + pfns[i] = pfn + (i % XEN_PFN_PER_PAGE); + } + } else + vma->vm_private_data = PRIV_VMA_LOCKED; + + memset(&xdata, 0, sizeof(xdata)); + xdata.domid = kdata.dom; + xdata.type = kdata.type; + xdata.id = kdata.id; + xdata.frame = kdata.idx; + xdata.nr_frames = kdata.num; + set_xen_guest_handle(xdata.frame_list, pfns); + + xen_preemptible_hcall_begin(); + rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata); + xen_preemptible_hcall_end(); + + if (rc) + goto out; + + if (xen_feature(XENFEAT_auto_translated_physmap)) { + struct remap_pfn r = { + .mm = vma->vm_mm, + .pages = vma->vm_private_data, + .prot = vma->vm_page_prot, + }; + + rc = apply_to_page_range(r.mm, kdata.addr, + kdata.num << PAGE_SHIFT, + remap_pfn_fn, &r); + } else { + unsigned int domid = + (xdata.flags & XENMEM_rsrc_acq_caller_owned) ? + DOMID_SELF : kdata.dom; + int num; + + num = xen_remap_domain_mfn_array(vma, + kdata.addr & PAGE_MASK, + pfns, kdata.num, (int *)pfns, + vma->vm_page_prot, + domid, + vma->vm_private_data); + if (num < 0) + rc = num; + else if (num != kdata.num) { + unsigned int i; + + for (i = 0; i < num; i++) { + rc = pfns[i]; + if (rc < 0) + break; + } + } else + rc = 0; + } + +out: + up_write(&mm->mmap_sem); + kfree(pfns); + + return rc; +} + static long privcmd_ioctl(struct file *file, unsigned int cmd, unsigned long data) { @@ -753,6 +882,10 @@ static long privcmd_ioctl(struct file *file, ret = privcmd_ioctl_restrict(file, udata); break; + case IOCTL_PRIVCMD_MMAP_RESOURCE: + ret = privcmd_ioctl_mmap_resource(file, udata); + break; + default: break; } diff --git a/include/uapi/xen/privcmd.h b/include/uapi/xen/privcmd.h index 39d3e7b8e993..d2029556083e 100644 --- a/include/uapi/xen/privcmd.h +++ b/include/uapi/xen/privcmd.h @@ -89,6 +89,15 @@ struct privcmd_dm_op { const struct privcmd_dm_op_buf __user *ubufs; }; +struct privcmd_mmap_resource { + domid_t dom; + __u32 type; + __u32 id; + __u32 idx; + __u64 num; + __u64 addr; +}; + /* * @cmd: IOCTL_PRIVCMD_HYPERCALL * @arg: &privcmd_hypercall_t @@ -114,5 +123,7 @@ struct privcmd_dm_op { _IOC(_IOC_NONE, 'P', 5, sizeof(struct privcmd_dm_op)) #define IOCTL_PRIVCMD_RESTRICT \ _IOC(_IOC_NONE, 'P', 6, sizeof(domid_t)) +#define IOCTL_PRIVCMD_MMAP_RESOURCE \ + _IOC(_IOC_NONE, 'P', 7, sizeof(struct privcmd_mmap_resource)) #endif /* __LINUX_PUBLIC_PRIVCMD_H__ */ diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index 583dd93b3016..4c5751c26f87 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -265,4 +265,70 @@ struct xen_remove_from_physmap { }; DEFINE_GUEST_HANDLE_STRUCT(xen_remove_from_physmap); +/* + * Get the pages for a particular guest resource, so that they can be + * mapped directly by a tools domain. + */ +#define XENMEM_acquire_resource 28 +struct xen_mem_acquire_resource { + /* IN - The domain whose resource is to be mapped */ + domid_t domid; + /* IN - the type of resource */ + uint16_t type; + +#define XENMEM_resource_ioreq_server 0 +#define XENMEM_resource_grant_table 1 + + /* + * IN - a type-specific resource identifier, which must be zero + * unless stated otherwise. + * + * type == XENMEM_resource_ioreq_server -> id == ioreq server id + * type == XENMEM_resource_grant_table -> id defined below + */ + uint32_t id; + +#define XENMEM_resource_grant_table_id_shared 0 +#define XENMEM_resource_grant_table_id_status 1 + + /* IN/OUT - As an IN parameter number of frames of the resource + * to be mapped. However, if the specified value is 0 and + * frame_list is NULL then this field will be set to the + * maximum value supported by the implementation on return. + */ + uint32_t nr_frames; + /* + * OUT - Must be zero on entry. On return this may contain a bitwise + * OR of the following values. + */ + uint32_t flags; + + /* The resource pages have been assigned to the calling domain */ +#define _XENMEM_rsrc_acq_caller_owned 0 +#define XENMEM_rsrc_acq_caller_owned (1u << _XENMEM_rsrc_acq_caller_owned) + + /* + * IN - the index of the initial frame to be mapped. This parameter + * is ignored if nr_frames is 0. + */ + uint64_t frame; + +#define XENMEM_resource_ioreq_server_frame_bufioreq 0 +#define XENMEM_resource_ioreq_server_frame_ioreq(n) (1 + (n)) + + /* + * IN/OUT - If the tools domain is PV then, upon return, frame_list + * will be populated with the MFNs of the resource. + * If the tools domain is HVM then it is expected that, on + * entry, frame_list will be populated with a list of GFNs + * that will be mapped to the MFNs of the resource. + * If -EIO is returned then the frame_list has only been + * partially mapped and it is up to the caller to unmap all + * the GFNs. + * This parameter may be NULL if nr_frames is 0. + */ + GUEST_HANDLE(xen_pfn_t) frame_list; +}; +DEFINE_GUEST_HANDLE_STRUCT(xen_mem_acquire_resource); + #endif /* __XEN_PUBLIC_MEMORY_H__ */ diff --git a/include/xen/interface/xen.h b/include/xen/interface/xen.h index 4f4830ef8f93..8bfb242f433e 100644 --- a/include/xen/interface/xen.h +++ b/include/xen/interface/xen.h @@ -265,9 +265,10 @@ * * PAT (bit 7 on) --> PWT (bit 3 on) and clear bit 7. */ -#define MMU_NORMAL_PT_UPDATE 0 /* checked '*ptr = val'. ptr is MA. */ -#define MMU_MACHPHYS_UPDATE 1 /* ptr = MA of frame to modify entry for */ -#define MMU_PT_UPDATE_PRESERVE_AD 2 /* atomically: *ptr = val | (*ptr&(A|D)) */ +#define MMU_NORMAL_PT_UPDATE 0 /* checked '*ptr = val'. ptr is MA. */ +#define MMU_MACHPHYS_UPDATE 1 /* ptr = MA of frame to modify entry for */ +#define MMU_PT_UPDATE_PRESERVE_AD 2 /* atomically: *ptr = val | (*ptr&(A|D)) */ +#define MMU_PT_UPDATE_NO_TRANSLATE 3 /* checked '*ptr = val'. ptr is MA. */ /* * MMU EXTENDED OPERATIONS diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h index fd23e42c6024..fd18c974a619 100644 --- a/include/xen/xen-ops.h +++ b/include/xen/xen-ops.h @@ -63,7 +63,7 @@ static inline void xen_destroy_contiguous_region(phys_addr_t pstart, struct vm_area_struct; /* - * xen_remap_domain_gfn_array() - map an array of foreign frames + * xen_remap_domain_gfn_array() - map an array of foreign frames by gfn * @vma: VMA to map the pages into * @addr: Address at which to map the pages * @gfn: Array of GFNs to map @@ -86,6 +86,28 @@ int xen_remap_domain_gfn_array(struct vm_area_struct *vma, unsigned domid, struct page **pages); +/* + * xen_remap_domain_mfn_array() - map an array of foreign frames by mfn + * @vma: VMA to map the pages into + * @addr: Address at which to map the pages + * @mfn: Array of MFNs to map + * @nr: Number entries in the MFN array + * @err_ptr: Returns per-MFN error status. + * @prot: page protection mask + * @domid: Domain owning the pages + * @pages: Array of pages if this domain has an auto-translated physmap + * + * @mfn and @err_ptr may point to the same buffer, the MFNs will be + * overwritten by the error codes after they are mapped. + * + * Returns the number of successfully mapped frames, or a -ve error + * code. + */ +int xen_remap_domain_mfn_array(struct vm_area_struct *vma, + unsigned long addr, xen_pfn_t *mfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, struct page **pages); + /* xen_remap_domain_gfn_range() - map a range of foreign frames * @vma: VMA to map the pages into * @addr: Address at which to map the pages From 24a94b3c1268635d64333ce58e7cc31ee5932125 Mon Sep 17 00:00:00 2001 From: Luc Van Oostenryck Date: Tue, 24 Apr 2018 15:18:14 +0200 Subject: [PATCH 3/6] xen-netfront: fix xennet_start_xmit()'s return type The method ndo_start_xmit() is defined as returning an 'netdev_tx_t', which is a typedef for an enum type, but the implementation in this driver returns an 'int'. Fix this by returning 'netdev_tx_t' in this driver too. Signed-off-by: Luc Van Oostenryck Reviewed-by: Wei Liu Signed-off-by: Juergen Gross --- drivers/net/xen-netfront.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 4dd0668003e7..679da1abd73c 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -564,7 +564,7 @@ static u16 xennet_select_queue(struct net_device *dev, struct sk_buff *skb, #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1) -static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) +static netdev_tx_t xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct netfront_info *np = netdev_priv(dev); struct netfront_stats *tx_stats = this_cpu_ptr(np->tx_stats); From 515e6541f54e90513fe4cd91f69d737a891f1c79 Mon Sep 17 00:00:00 2001 From: Roger Pau Monne Date: Wed, 9 May 2018 11:21:28 +0100 Subject: [PATCH 4/6] xen/store: do not store local values in xen_start_info MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There's no need to store the xenstore page or event channel in xen_start_info if they are locally initialized. This also fixes PVH local xenstore initialization due to the lack of xen_start_info in that case. Signed-off-by: Boris Ostrovsky Signed-off-by: Roger Pau Monné Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross --- drivers/xen/xenbus/xenbus_probe.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index ec9eb4fba59c..f2088838f690 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -710,7 +710,7 @@ static int __init xenstored_local_init(void) if (!page) goto out_err; - xen_store_gfn = xen_start_info->store_mfn = virt_to_gfn((void *)page); + xen_store_gfn = virt_to_gfn((void *)page); /* Next allocate a local port which xenstored can bind to */ alloc_unbound.dom = DOMID_SELF; @@ -722,8 +722,7 @@ static int __init xenstored_local_init(void) goto out_err; BUG_ON(err); - xen_store_evtchn = xen_start_info->store_evtchn = - alloc_unbound.port; + xen_store_evtchn = alloc_unbound.port; return 0; From 98014068328c5574de9a4a30b604111fd9d8f901 Mon Sep 17 00:00:00 2001 From: Boris Ostrovsky Date: Tue, 8 May 2018 19:56:22 -0400 Subject: [PATCH 5/6] xen/PVH: Set up GS segment for stack canary We are making calls to C code (e.g. xen_prepare_pvh()) which may use stack canary (stored in GS segment). Signed-off-by: Boris Ostrovsky Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross --- arch/x86/xen/xen-pvh.S | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/xen/xen-pvh.S index e1a5fbeae08d..5d7554c025fd 100644 --- a/arch/x86/xen/xen-pvh.S +++ b/arch/x86/xen/xen-pvh.S @@ -54,6 +54,9 @@ * charge of setting up it's own stack, GDT and IDT. */ +#define PVH_GDT_ENTRY_CANARY 4 +#define PVH_CANARY_SEL (PVH_GDT_ENTRY_CANARY * 8) + ENTRY(pvh_start_xen) cld @@ -98,6 +101,12 @@ ENTRY(pvh_start_xen) /* 64-bit entry point. */ .code64 1: + /* Set base address in stack canary descriptor. */ + mov $MSR_GS_BASE,%ecx + mov $_pa(canary), %eax + xor %edx, %edx + wrmsr + call xen_prepare_pvh /* startup_64 expects boot_params in %rsi. */ @@ -107,6 +116,17 @@ ENTRY(pvh_start_xen) #else /* CONFIG_X86_64 */ + /* Set base address in stack canary descriptor. */ + movl $_pa(gdt_start),%eax + movl $_pa(canary),%ecx + movw %cx, (PVH_GDT_ENTRY_CANARY * 8) + 2(%eax) + shrl $16, %ecx + movb %cl, (PVH_GDT_ENTRY_CANARY * 8) + 4(%eax) + movb %ch, (PVH_GDT_ENTRY_CANARY * 8) + 7(%eax) + + mov $PVH_CANARY_SEL,%eax + mov %eax,%gs + call mk_early_pgtbl_32 mov $_pa(initial_page_table), %eax @@ -150,9 +170,13 @@ gdt_start: .quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* __KERNEL_CS */ #endif .quad GDT_ENTRY(0xc092, 0, 0xfffff) /* __KERNEL_DS */ + .quad GDT_ENTRY(0x4090, 0, 0x18) /* PVH_CANARY_SEL */ gdt_end: - .balign 4 + .balign 16 +canary: + .fill 48, 1, 0 + early_stack: .fill 256, 1, 0 early_stack_end: From 7f47e1c52d0c850cbd24aab763ce6bab11bdb4b2 Mon Sep 17 00:00:00 2001 From: Boris Ostrovsky Date: Tue, 8 May 2018 20:25:54 -0400 Subject: [PATCH 6/6] xen/PVH: Make GDT selectors PVH-specific We don't need to share PVH GDT layout with other GDTs, especially since we now have a PVH-speciific entry (for stack canary segment). Define PVH's own selectors. (As a side effect of this change we are also fixing improper reference to __KERNEL_CS) Signed-off-by: Boris Ostrovsky Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross --- arch/x86/xen/xen-pvh.S | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/xen/xen-pvh.S index 5d7554c025fd..ca2d3b2bf2af 100644 --- a/arch/x86/xen/xen-pvh.S +++ b/arch/x86/xen/xen-pvh.S @@ -54,7 +54,11 @@ * charge of setting up it's own stack, GDT and IDT. */ -#define PVH_GDT_ENTRY_CANARY 4 +#define PVH_GDT_ENTRY_CS 1 +#define PVH_GDT_ENTRY_DS 2 +#define PVH_GDT_ENTRY_CANARY 3 +#define PVH_CS_SEL (PVH_GDT_ENTRY_CS * 8) +#define PVH_DS_SEL (PVH_GDT_ENTRY_DS * 8) #define PVH_CANARY_SEL (PVH_GDT_ENTRY_CANARY * 8) ENTRY(pvh_start_xen) @@ -62,7 +66,7 @@ ENTRY(pvh_start_xen) lgdt (_pa(gdt)) - mov $(__BOOT_DS),%eax + mov $PVH_DS_SEL,%eax mov %eax,%ds mov %eax,%es mov %eax,%ss @@ -96,7 +100,7 @@ ENTRY(pvh_start_xen) mov %eax, %cr0 /* Jump to 64-bit mode. */ - ljmp $__KERNEL_CS, $_pa(1f) + ljmp $PVH_CS_SEL, $_pa(1f) /* 64-bit entry point. */ .code64 @@ -136,13 +140,13 @@ ENTRY(pvh_start_xen) or $(X86_CR0_PG | X86_CR0_PE), %eax mov %eax, %cr0 - ljmp $__BOOT_CS, $1f + ljmp $PVH_CS_SEL, $1f 1: call xen_prepare_pvh mov $_pa(pvh_bootparams), %esi /* startup_32 doesn't expect paging and PAE to be on. */ - ljmp $__BOOT_CS, $_pa(2f) + ljmp $PVH_CS_SEL, $_pa(2f) 2: mov %cr0, %eax and $~X86_CR0_PG, %eax @@ -151,7 +155,7 @@ ENTRY(pvh_start_xen) and $~X86_CR4_PAE, %eax mov %eax, %cr4 - ljmp $__BOOT_CS, $_pa(startup_32) + ljmp $PVH_CS_SEL, $_pa(startup_32) #endif END(pvh_start_xen) @@ -163,13 +167,12 @@ gdt: .word 0 gdt_start: .quad 0x0000000000000000 /* NULL descriptor */ - .quad 0x0000000000000000 /* reserved */ #ifdef CONFIG_X86_64 - .quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* __KERNEL_CS */ + .quad GDT_ENTRY(0xa09a, 0, 0xfffff) /* PVH_CS_SEL */ #else - .quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* __KERNEL_CS */ + .quad GDT_ENTRY(0xc09a, 0, 0xfffff) /* PVH_CS_SEL */ #endif - .quad GDT_ENTRY(0xc092, 0, 0xfffff) /* __KERNEL_DS */ + .quad GDT_ENTRY(0xc092, 0, 0xfffff) /* PVH_DS_SEL */ .quad GDT_ENTRY(0x4090, 0, 0x18) /* PVH_CANARY_SEL */ gdt_end: