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| author | Juergen Gross <jgross@suse.com> | 2015-03-20 15:55:39 +0300 |
|---|---|---|
| committer | Luis Henriques <luis.henriques@canonical.com> | 2015-04-13 18:48:56 +0300 |
| commit | e880e9b18274e10fc38b1491fa580b7002cb2c10 (patch) | |
| tree | ffefa6d6289954ba9790bd2b853c04d025e9e5ec | |
| parent | 88772980d6b3278c1c24885bf0fdf8d149769824 (diff) | |
| download | linux-e880e9b18274e10fc38b1491fa580b7002cb2c10.tar.xz | |
xen/balloon: before adding hotplugged memory, set frames to invalid
commit 3c56b3a12ce52f361468cbdd2f79b2f3b8da0ea6 upstream.
Commit 25b884a83d487fd62c3de7ac1ab5549979188482 ("x86/xen: set
regions above the end of RAM as 1:1") introduced a regression.
To be able to add memory pages which were added via memory hotplug to
a pv domain, the pages must be "invalid" instead of "identity" in the
p2m list before they can be added.
Suggested-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
| -rw-r--r-- | drivers/xen/balloon.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index 5c660c77f03b..8db7abb6ef5a 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -227,6 +227,29 @@ static enum bp_state reserve_additional_memory(long credit) balloon_hotplug = round_up(balloon_hotplug, PAGES_PER_SECTION); nid = memory_add_physaddr_to_nid(hotplug_start_paddr); +#ifdef CONFIG_XEN_HAVE_PVMMU + /* + * add_memory() will build page tables for the new memory so + * the p2m must contain invalid entries so the correct + * non-present PTEs will be written. + * + * If a failure occurs, the original (identity) p2m entries + * are not restored since this region is now known not to + * conflict with any devices. + */ + if (!xen_feature(XENFEAT_auto_translated_physmap)) { + unsigned long pfn, i; + + pfn = PFN_DOWN(hotplug_start_paddr); + for (i = 0; i < balloon_hotplug; i++) { + if (!set_phys_to_machine(pfn + i, INVALID_P2M_ENTRY)) { + pr_warn("set_phys_to_machine() failed, no memory added\n"); + return BP_ECANCELED; + } + } + } +#endif + rc = add_memory(nid, hotplug_start_paddr, balloon_hotplug << PAGE_SHIFT); if (rc) { |