From d9cccfa7c4d1d9ef967ec9308df7304a18609b30 Mon Sep 17 00:00:00 2001 From: Liam Merwick Date: Fri, 2 Nov 2018 14:04:23 +0000 Subject: xen/grant-table: Fix incorrect gnttab_dma_free_pages() pr_debug message If a call to xenmem_reservation_increase() in gnttab_dma_free_pages() fails it triggers a message "Failed to decrease reservation..." which should be "Failed to increase reservation..." Fixes: 9bdc7304f536 ('xen/grant-table: Allow allocating buffers suitable for DMA') Reported-by: Ross Philipson Signed-off-by: Liam Merwick Reviewed-by: Mark Kanda Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross --- drivers/xen/grant-table.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/xen') diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 84575baceebc..97341fa75458 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -914,7 +914,7 @@ int gnttab_dma_free_pages(struct gnttab_dma_alloc_args *args) ret = xenmem_reservation_increase(args->nr_pages, args->frames); if (ret != args->nr_pages) { - pr_debug("Failed to decrease reservation for DMA buffer\n"); + pr_debug("Failed to increase reservation for DMA buffer\n"); ret = -EFAULT; } else { ret = 0; -- cgit v1.2.3 From 3941552aec1e04d63999988a057ae09a1c56ebeb Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Thu, 1 Nov 2018 13:33:07 +0100 Subject: xen: remove size limit of privcmd-buf mapping interface Currently the size of hypercall buffers allocated via /dev/xen/hypercall is limited to a default of 64 memory pages. For live migration of guests this might be too small as the page dirty bitmask needs to be sized according to the size of the guest. This means migrating a 8GB sized guest is already exhausting the default buffer size for the dirty bitmap. There is no sensible way to set a sane limit, so just remove it completely. The device node's usage is limited to root anyway, so there is no additional DOS scenario added by allowing unlimited buffers. While at it make the error path for the -ENOMEM case a little bit cleaner by setting n_pages to the number of successfully allocated pages instead of the target size. Fixes: c51b3c639e01f2 ("xen: add new hypercall buffer mapping device") Cc: #4.18 Signed-off-by: Juergen Gross Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross --- drivers/xen/privcmd-buf.c | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-) (limited to 'drivers/xen') diff --git a/drivers/xen/privcmd-buf.c b/drivers/xen/privcmd-buf.c index df1ed37c3269..de01a6d0059d 100644 --- a/drivers/xen/privcmd-buf.c +++ b/drivers/xen/privcmd-buf.c @@ -21,15 +21,9 @@ MODULE_LICENSE("GPL"); -static unsigned int limit = 64; -module_param(limit, uint, 0644); -MODULE_PARM_DESC(limit, "Maximum number of pages that may be allocated by " - "the privcmd-buf device per open file"); - struct privcmd_buf_private { struct mutex lock; struct list_head list; - unsigned int allocated; }; struct privcmd_buf_vma_private { @@ -60,13 +54,10 @@ static void privcmd_buf_vmapriv_free(struct privcmd_buf_vma_private *vma_priv) { unsigned int i; - vma_priv->file_priv->allocated -= vma_priv->n_pages; - list_del(&vma_priv->list); for (i = 0; i < vma_priv->n_pages; i++) - if (vma_priv->pages[i]) - __free_page(vma_priv->pages[i]); + __free_page(vma_priv->pages[i]); kfree(vma_priv); } @@ -146,8 +137,7 @@ static int privcmd_buf_mmap(struct file *file, struct vm_area_struct *vma) unsigned int i; int ret = 0; - if (!(vma->vm_flags & VM_SHARED) || count > limit || - file_priv->allocated + count > limit) + if (!(vma->vm_flags & VM_SHARED)) return -EINVAL; vma_priv = kzalloc(sizeof(*vma_priv) + count * sizeof(void *), @@ -155,19 +145,15 @@ static int privcmd_buf_mmap(struct file *file, struct vm_area_struct *vma) if (!vma_priv) return -ENOMEM; - vma_priv->n_pages = count; - count = 0; - for (i = 0; i < vma_priv->n_pages; i++) { + for (i = 0; i < count; i++) { vma_priv->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO); if (!vma_priv->pages[i]) break; - count++; + vma_priv->n_pages++; } mutex_lock(&file_priv->lock); - file_priv->allocated += count; - vma_priv->file_priv = file_priv; vma_priv->users = 1; -- cgit v1.2.3 From 72791ac854fea36034fa7976b748fde585008e78 Mon Sep 17 00:00:00 2001 From: Srikanth Boddepalli Date: Tue, 27 Nov 2018 19:53:27 +0530 Subject: xen: xlate_mmu: add missing header to fix 'W=1' warning Add a missing header otherwise compiler warns about missed prototype: drivers/xen/xlate_mmu.c:183:5: warning: no previous prototype for 'xen_xlate_unmap_gfn_range?' [-Wmissing-prototypes] int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma, ^~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Srikanth Boddepalli Reviewed-by: Boris Ostrovsky Reviewed-by: Joey Pabalinas Signed-off-by: Juergen Gross --- drivers/xen/xlate_mmu.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/xen') diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c index 23f1387b3ef7..e7df65d32c91 100644 --- a/drivers/xen/xlate_mmu.c +++ b/drivers/xen/xlate_mmu.c @@ -36,6 +36,7 @@ #include #include +#include #include #include #include -- cgit v1.2.3 From 123664101aa2156d05251704fc63f9bcbf77741a Mon Sep 17 00:00:00 2001 From: Igor Druzhinin Date: Tue, 27 Nov 2018 20:58:21 +0000 Subject: Revert "xen/balloon: Mark unallocated host memory as UNUSABLE" This reverts commit b3cf8528bb21febb650a7ecbf080d0647be40b9f. That commit unintentionally broke Xen balloon memory hotplug with "hotplug_unpopulated" set to 1. As long as "System RAM" resource got assigned under a new "Unusable memory" resource in IO/Mem tree any attempt to online this memory would fail due to general kernel restrictions on having "System RAM" resources as 1st level only. The original issue that commit has tried to workaround fa564ad96366 ("x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f, 60-7f)") also got amended by the following 03a551734 ("x86/PCI: Move and shrink AMD 64-bit window to avoid conflict") which made the original fix to Xen ballooning unnecessary. Signed-off-by: Igor Druzhinin Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross --- drivers/xen/balloon.c | 65 +++++++-------------------------------------------- 1 file changed, 9 insertions(+), 56 deletions(-) (limited to 'drivers/xen') diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index e12bb256036f..7ab6caef599c 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -251,25 +251,10 @@ static void release_memory_resource(struct resource *resource) kfree(resource); } -/* - * Host memory not allocated to dom0. We can use this range for hotplug-based - * ballooning. - * - * It's a type-less resource. Setting IORESOURCE_MEM will make resource - * management algorithms (arch_remove_reservations()) look into guest e820, - * which we don't want. - */ -static struct resource hostmem_resource = { - .name = "Host RAM", -}; - -void __attribute__((weak)) __init arch_xen_balloon_init(struct resource *res) -{} - static struct resource *additional_memory_resource(phys_addr_t size) { - struct resource *res, *res_hostmem; - int ret = -ENOMEM; + struct resource *res; + int ret; res = kzalloc(sizeof(*res), GFP_KERNEL); if (!res) @@ -278,42 +263,13 @@ static struct resource *additional_memory_resource(phys_addr_t size) res->name = "System RAM"; res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - res_hostmem = kzalloc(sizeof(*res), GFP_KERNEL); - if (res_hostmem) { - /* Try to grab a range from hostmem */ - res_hostmem->name = "Host memory"; - ret = allocate_resource(&hostmem_resource, res_hostmem, - size, 0, -1, - PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL); - } - - if (!ret) { - /* - * Insert this resource into iomem. Because hostmem_resource - * tracks portion of guest e820 marked as UNUSABLE noone else - * should try to use it. - */ - res->start = res_hostmem->start; - res->end = res_hostmem->end; - ret = insert_resource(&iomem_resource, res); - if (ret < 0) { - pr_err("Can't insert iomem_resource [%llx - %llx]\n", - res->start, res->end); - release_memory_resource(res_hostmem); - res_hostmem = NULL; - res->start = res->end = 0; - } - } - - if (ret) { - ret = allocate_resource(&iomem_resource, res, - size, 0, -1, - PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL); - if (ret < 0) { - pr_err("Cannot allocate new System RAM resource\n"); - kfree(res); - return NULL; - } + ret = allocate_resource(&iomem_resource, res, + size, 0, -1, + PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL); + if (ret < 0) { + pr_err("Cannot allocate new System RAM resource\n"); + kfree(res); + return NULL; } #ifdef CONFIG_SPARSEMEM @@ -325,7 +281,6 @@ static struct resource *additional_memory_resource(phys_addr_t size) pr_err("New System RAM resource outside addressable RAM (%lu > %lu)\n", pfn, limit); release_memory_resource(res); - release_memory_resource(res_hostmem); return NULL; } } @@ -747,8 +702,6 @@ static int __init balloon_init(void) set_online_page_callback(&xen_online_page); register_memory_notifier(&xen_memory_nb); register_sysctl_table(xen_root); - - arch_xen_balloon_init(&hostmem_resource); #endif #ifdef CONFIG_XEN_PV -- cgit v1.2.3 From 975ef94a0284648fb0137bd5e949b18cef604e33 Mon Sep 17 00:00:00 2001 From: Pan Bian Date: Thu, 22 Nov 2018 10:07:12 +0800 Subject: pvcalls-front: fixes incorrect error handling kfree() is incorrectly used to release the pages allocated by __get_free_page() and __get_free_pages(). Use the matching deallocators i.e., free_page() and free_pages(), respectively. Signed-off-by: Pan Bian Reviewed-by: Stefano Stabellini Signed-off-by: Juergen Gross --- drivers/xen/pvcalls-front.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/xen') diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index 2f11ca72a281..77224d8f3e6f 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -385,8 +385,8 @@ static int create_active(struct sock_mapping *map, int *evtchn) out_error: if (*evtchn >= 0) xenbus_free_evtchn(pvcalls_front_dev, *evtchn); - kfree(map->active.data.in); - kfree(map->active.ring); + free_pages((unsigned long)map->active.data.in, PVCALLS_RING_ORDER); + free_page((unsigned long)map->active.ring); return ret; } -- cgit v1.2.3