diff options
Diffstat (limited to 'sysutils/xen-tools/files/xsa125.patch')
| -rw-r--r-- | sysutils/xen-tools/files/xsa125.patch | 154 |
1 files changed, 0 insertions, 154 deletions
diff --git a/sysutils/xen-tools/files/xsa125.patch b/sysutils/xen-tools/files/xsa125.patch deleted file mode 100644 index ad5dbb31c204..000000000000 --- a/sysutils/xen-tools/files/xsa125.patch +++ /dev/null @@ -1,154 +0,0 @@ -From 98670acc98cad5aee0e0714694a64d3b96675c36 Mon Sep 17 00:00:00 2001 -From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> -Date: Wed, 19 Nov 2014 12:57:11 -0500 -Subject: [PATCH] Limit XEN_DOMCTL_memory_mapping hypercall to only process up - to 64 GFNs (or less) - -Said hypercall for large BARs can take quite a while. As such -we can require that the hypercall MUST break up the request -in smaller values. - -Another approach is to add preemption to it - whether we do the -preemption using hypercall_create_continuation or returning -EAGAIN to userspace (and have it re-invocate the call) - either -way the issue we cannot easily solve is that in 'map_mmio_regions' -if we encounter an error we MUST call 'unmap_mmio_regions' for the -whole BAR region. - -Since the preemption would re-use input fields such as nr_mfns, -first_gfn, first_mfn - we would lose the original values - -and only undo what was done in the current round (i.e. ignoring -anything that was done prior to earlier preemptions). - -Unless we re-used the return value as 'EAGAIN|nr_mfns_done<<10' but -that puts a limit (since the return value is a long) on the amount -of nr_mfns that can provided. - -This patch sidesteps this problem by: - - Setting an hard limit of nr_mfns having to be 64 or less. - - Toolstack adjusts correspondingly to the nr_mfn limit. - - If the there is an error when adding the toolstack will call the - remove operation to remove the whole region. - -The need to break this hypercall down is for large BARs can take -more than the guest (initial domain usually) time-slice. This has -the negative result in that the guest is locked out for a long -duration and is unable to act on any pending events. - -We also augment the code to return zero if nr_mfns instead -of trying to the hypercall. - -Suggested-by: Jan Beulich <jbeulich@suse.com> -Acked-by: Jan Beulich <jbeulich@suse.com> -Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> -Acked-by: Ian Campbell <ian.campbell@citrix.com> ---- -[v50: Simplify loop] -[v51: If max_batch_sz 1 (or less) we would return zero. Fix that] -[v52: Handle nr_mfns being zero] -[v53: Fix up return value] ---- - tools/libxc/xc_domain.c | 46 +++++++++++++++++++++++++++++++++++++++++---- - xen/common/domctl.c | 5 +++++ - xen/include/public/domctl.h | 1 + - 3 files changed, 48 insertions(+), 4 deletions(-) - -diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c -index 845d1d7..bba7672 100644 ---- a/tools/libxc/xc_domain.c -+++ b/tools/libxc/xc_domain.c -@@ -1988,6 +1988,8 @@ int xc_domain_memory_mapping( - { - DECLARE_DOMCTL; - xc_dominfo_t info; -+ int ret = 0, err; -+ unsigned long done = 0, nr, max_batch_sz; - - if ( xc_domain_getinfo(xch, domid, 1, &info) != 1 || - info.domid != domid ) -@@ -1998,14 +2000,50 @@ int xc_domain_memory_mapping( - if ( !xc_core_arch_auto_translated_physmap(&info) ) - return 0; - -+ if ( !nr_mfns ) -+ return 0; -+ - domctl.cmd = XEN_DOMCTL_memory_mapping; - domctl.domain = domid; -- domctl.u.memory_mapping.first_gfn = first_gfn; -- domctl.u.memory_mapping.first_mfn = first_mfn; -- domctl.u.memory_mapping.nr_mfns = nr_mfns; - domctl.u.memory_mapping.add_mapping = add_mapping; -+ max_batch_sz = nr_mfns; -+ do -+ { -+ nr = min(nr_mfns - done, max_batch_sz); -+ domctl.u.memory_mapping.nr_mfns = nr; -+ domctl.u.memory_mapping.first_gfn = first_gfn + done; -+ domctl.u.memory_mapping.first_mfn = first_mfn + done; -+ err = do_domctl(xch, &domctl); -+ if ( err && errno == E2BIG ) -+ { -+ if ( max_batch_sz <= 1 ) -+ break; -+ max_batch_sz >>= 1; -+ continue; -+ } -+ /* Save the first error... */ -+ if ( !ret ) -+ ret = err; -+ /* .. and ignore the rest of them when removing. */ -+ if ( err && add_mapping != DPCI_REMOVE_MAPPING ) -+ break; - -- return do_domctl(xch, &domctl); -+ done += nr; -+ } while ( done < nr_mfns ); -+ -+ /* -+ * Undo what we have done unless unmapping, by unmapping the entire region. -+ * Errors here are ignored. -+ */ -+ if ( ret && add_mapping != DPCI_REMOVE_MAPPING ) -+ xc_domain_memory_mapping(xch, domid, first_gfn, first_mfn, nr_mfns, -+ DPCI_REMOVE_MAPPING); -+ -+ /* We might get E2BIG so many times that we never advance. */ -+ if ( !done && !ret ) -+ ret = -1; -+ -+ return ret; - } - - int xc_domain_ioport_mapping( -diff --git a/xen/common/domctl.c b/xen/common/domctl.c -index d396cc4..c2e60a7 100644 ---- a/xen/common/domctl.c -+++ b/xen/common/domctl.c -@@ -1027,6 +1027,11 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl) - (gfn + nr_mfns - 1) < gfn ) /* wrap? */ - break; - -+ ret = -E2BIG; -+ /* Must break hypercall up as this could take a while. */ -+ if ( nr_mfns > 64 ) -+ break; -+ - ret = -EPERM; - if ( !iomem_access_permitted(current->domain, mfn, mfn_end) || - !iomem_access_permitted(d, mfn, mfn_end) ) -diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h -index ca0e51e..0c9f474 100644 ---- a/xen/include/public/domctl.h -+++ b/xen/include/public/domctl.h -@@ -543,6 +543,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_domctl_bind_pt_irq_t); - - - /* Bind machine I/O address range -> HVM address range. */ -+/* If this returns -E2BIG lower nr_mfns value. */ - /* XEN_DOMCTL_memory_mapping */ - #define DPCI_ADD_MAPPING 1 - #define DPCI_REMOVE_MAPPING 0 --- -2.1.0 - |