kernel/linux.git/drivers/xen/balloon.c, branch linux-4.16.y

xen/balloon: Mark unallocated host memory as UNUSABLE

2017-12-20T18:16:20+00:00

Commit f5775e0b6116 ("x86/xen: discard RAM regions above the maximum reservation") left host memory not assigned to dom0 as available for memory hotplug. Unfortunately this also meant that those regions could be used by others. Specifically, commit fa564ad96366 ("x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f, 60-7f)") may try to map those addresses as MMIO. To prevent this mark unallocated host memory as E820_TYPE_UNUSABLE (thus effectively reverting f5775e0b6116) and keep track of that region as a hostmem resource that can be used for the hotplug. Signed-off-by: Boris Ostrovsky Reviewed-by: Juergen Gross

xen: Don't try to call xen_alloc_p2m_entry() on autotranslating guests

2017-08-31T13:45:55+00:00

Commit aba831a69632 ("xen: remove tests for pvh mode in pure pv paths") removed XENFEAT_auto_translated_physmap test in xen_alloc_p2m_entry() since it is assumed that the routine is never called by non-PV guests. However, alloc_xenballooned_pages() may make this call on a PVH guest. Prevent this from happening by adding XENFEAT_auto_translated_physmap check there. Signed-off-by: Boris Ostrovsky Reviewed-by: Juergen Gross Fixes: aba831a69632 ("xen: remove tests for pvh mode in pure pv paths")

xen/balloon: don't online new memory initially

2017-07-23T06:13:18+00:00

When setting up the Xenstore watch for the memory target size the new watch will fire at once. Don't try to reach the configured target size by onlining new memory in this case, as the current memory size will be smaller in almost all cases due to e.g. BIOS reserved pages. Onlining new memory will lead to more problems e.g. undesired conflicts with NVMe devices meant to be operated as block devices. Instead remember the difference between target size and current size when the watch fires for the first time and apply it to any further size changes, too. In order to avoid races between balloon.c and xen-balloon.c init calls do the xen-balloon.c initialization from balloon.c. Signed-off-by: Juergen Gross Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross

xen/balloon: decorate PV-only parts with #ifdef CONFIG_XEN_PV

2017-05-02T09:09:56+00:00

Balloon driver uses several PV-only concepts (xen_start_info, xen_extra_mem,..) and it seems the simpliest solution to make HVM-only build happy is to decorate these parts with #ifdefs. Signed-off-by: Vitaly Kuznetsov Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross

sched/headers: Prepare to remove inclusion from

2017-03-02T07:42:31+00:00

Add #include dependencies to all .c files rely on sched.h doing that for them. Note that even if the count where we need to add extra headers seems high, it's still a net win, because is included in over 2,200 files ... Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

xen/balloon: Only mark a page as managed when it is released

2016-12-12T14:22:22+00:00

Only mark a page as managed when it is released back to the allocator. This ensures that the managed page count does not get falsely increased when a VM is running. Correspondingly change it so that pages are marked as unmanaged after getting them from the allocator. Signed-off-by: Ross Lagerwall Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross

xen/balloon: Fix declared-but-not-defined warning

2016-06-23T10:36:15+00:00

Fix a declared-but-not-defined warning when building with XEN_BALLOON_MEMORY_HOTPLUG=n. This fixes a regression introduced by commit dfd74a1edfab ("xen/balloon: Fix crash when ballooning on x86 32 bit PAE"). Signed-off-by: Ross Lagerwall Acked-by: Juergen Gross Signed-off-by: David Vrabel

xen/balloon: Fix crash when ballooning on x86 32 bit PAE

2016-04-06T10:29:18+00:00

Commit 55b3da98a40dbb3776f7454daf0d95dde25c33d2 (xen/balloon: find non-conflicting regions to place hotplugged memory) caused a regression in 4.4. When ballooning on an x86 32 bit PAE system with close to 64 GiB of memory, the address returned by allocate_resource may be above 64 GiB. When using CONFIG_SPARSEMEM, this setup is limited to using physical addresses < 64 GiB. When adding memory at this address, it runs off the end of the mem_section array and causes a crash. Instead, fail the ballooning request. Signed-off-by: Ross Lagerwall Cc: # 4.4+ Signed-off-by: David Vrabel

Merge tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2016-03-22T19:55:17+00:00

Pull xen updates from David Vrabel: "Features and fixes for 4.6: - Make earlyprintk=xen work for HVM guests - Remove module support for things never built as modules" * tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: drivers/xen: make platform-pci.c explicitly non-modular drivers/xen: make sys-hypervisor.c explicitly non-modular drivers/xen: make xenbus_dev_[front/back]end explicitly non-modular drivers/xen: make [xen-]ballon explicitly non-modular xen: audit usages of module.h ; remove unnecessary instances xen/x86: Drop mode-selecting ifdefs in startup_xen() xen/x86: Zero out .bss for PV guests hvc_xen: make early_printk work with HVM guests hvc_xen: fix xenboot for DomUs hvc_xen: add earlycon support

drivers/xen: make [xen-]ballon explicitly non-modular

2016-03-21T15:13:44+00:00

The Makefile / Kconfig currently controlling compilation here is: obj-y += grant-table.o features.o balloon.o manage.o preempt.o time.o [...] obj-$(CONFIG_XEN_BALLOON) += xen-balloon.o ...with: drivers/xen/Kconfig:config XEN_BALLOON drivers/xen/Kconfig: bool "Xen memory balloon driver" ...meaning that they currently are not being built as modules by anyone. Lets remove the modular code that is essentially orphaned, so that when reading the driver there is no doubt it is builtin-only. In doing so we uncover two implict includes that were obtained by module.h having such a wide include scope itself: In file included from drivers/xen/xen-balloon.c:41:0: include/xen/balloon.h:26:51: warning: ‘struct page’ declared inside parameter list [enabled by default] int alloc_xenballooned_pages(int nr_pages, struct page **pages); ^ include/xen/balloon.h: In function ‘register_xen_selfballooning’: include/xen/balloon.h:35:10: error: ‘ENOSYS’ undeclared (first use in this function) return -ENOSYS; ^ This is fixed by adding mm-types.h and errno.h to the list. We also delete the MODULE_LICENSE tags since all that information is already contained at the top of the file in the comments. Signed-off-by: Paul Gortmaker Reviewed-by: Stefano Stabellini Signed-off-by: David Vrabel