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-rw-r--r--arch/x86/xen/Kconfig1
-rw-r--r--arch/x86/xen/enlighten.c32
-rw-r--r--arch/x86/xen/enlighten_pv.c11
-rw-r--r--arch/x86/xen/enlighten_pvh.c68
-rw-r--r--arch/x86/xen/setup.c44
-rw-r--r--arch/x86/xen/smp_pv.c4
-rw-r--r--arch/x86/xen/xen-head.S2
-rw-r--r--arch/x86/xen/xen-ops.h14
8 files changed, 127 insertions, 49 deletions
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index a65fc2ae15b4..77e788e928cd 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -81,7 +81,6 @@ config XEN_PVH
bool "Xen PVH guest support"
depends on XEN && XEN_PVHVM && ACPI
select PVH
- def_bool n
help
Support for running as a Xen PVH guest.
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 7030a6aa9670..5f3a69f6ec34 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -3,6 +3,7 @@
#include <linux/console.h>
#include <linux/cpu.h>
#include <linux/kexec.h>
+#include <linux/memblock.h>
#include <linux/slab.h>
#include <linux/panic_notifier.h>
@@ -347,3 +348,34 @@ void xen_arch_unregister_cpu(int num)
}
EXPORT_SYMBOL(xen_arch_unregister_cpu);
#endif
+
+/* Amount of extra memory space we add to the e820 ranges */
+struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
+
+void __init xen_add_extra_mem(unsigned long start_pfn, unsigned long n_pfns)
+{
+ unsigned int i;
+
+ /*
+ * No need to check for zero size, should happen rarely and will only
+ * write a new entry regarded to be unused due to zero size.
+ */
+ for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
+ /* Add new region. */
+ if (xen_extra_mem[i].n_pfns == 0) {
+ xen_extra_mem[i].start_pfn = start_pfn;
+ xen_extra_mem[i].n_pfns = n_pfns;
+ break;
+ }
+ /* Append to existing region. */
+ if (xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns ==
+ start_pfn) {
+ xen_extra_mem[i].n_pfns += n_pfns;
+ break;
+ }
+ }
+ if (i == XEN_EXTRA_MEM_MAX_REGIONS)
+ printk(KERN_WARNING "Warning: not enough extra memory regions\n");
+
+ memblock_reserve(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns));
+}
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index ace2eb054053..9ba53814ed6a 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -219,13 +219,21 @@ static __read_mostly unsigned int cpuid_leaf5_edx_val;
static void xen_cpuid(unsigned int *ax, unsigned int *bx,
unsigned int *cx, unsigned int *dx)
{
- unsigned maskebx = ~0;
+ unsigned int maskebx = ~0;
+ unsigned int or_ebx = 0;
/*
* Mask out inconvenient features, to try and disable as many
* unsupported kernel subsystems as possible.
*/
switch (*ax) {
+ case 0x1:
+ /* Replace initial APIC ID in bits 24-31 of EBX. */
+ /* See xen_pv_smp_config() for related topology preparations. */
+ maskebx = 0x00ffffff;
+ or_ebx = smp_processor_id() << 24;
+ break;
+
case CPUID_MWAIT_LEAF:
/* Synthesize the values.. */
*ax = 0;
@@ -248,6 +256,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
: "0" (*ax), "2" (*cx));
*bx &= maskebx;
+ *bx |= or_ebx;
}
static bool __init xen_check_mwait(void)
diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index 9e9db601bd52..27a2a02ef8fb 100644
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/acpi.h>
#include <linux/export.h>
+#include <linux/mm.h>
#include <xen/hvc-console.h>
@@ -73,3 +74,70 @@ void __init mem_map_via_hcall(struct boot_params *boot_params_p)
}
boot_params_p->e820_entries = memmap.nr_entries;
}
+
+/*
+ * Reserve e820 UNUSABLE regions to inflate the memory balloon.
+ *
+ * On PVH dom0 the host memory map is used, RAM regions available to dom0 are
+ * located as the same place as in the native memory map, but since dom0 gets
+ * less memory than the total amount of host RAM the ranges that can't be
+ * populated are converted from RAM -> UNUSABLE. Use such regions (up to the
+ * ratio signaled in EXTRA_MEM_RATIO) in order to inflate the balloon driver at
+ * boot. Doing so prevents the guest (even if just temporary) from using holes
+ * in the memory map in order to map grants or foreign addresses, and
+ * hopefully limits the risk of a clash with a device MMIO region. Ideally the
+ * hypervisor should notify us which memory ranges are suitable for creating
+ * foreign mappings, but that's not yet implemented.
+ */
+void __init xen_reserve_extra_memory(struct boot_params *bootp)
+{
+ unsigned int i, ram_pages = 0, extra_pages;
+
+ for (i = 0; i < bootp->e820_entries; i++) {
+ struct boot_e820_entry *e = &bootp->e820_table[i];
+
+ if (e->type != E820_TYPE_RAM)
+ continue;
+ ram_pages += PFN_DOWN(e->addr + e->size) - PFN_UP(e->addr);
+ }
+
+ /* Max amount of extra memory. */
+ extra_pages = EXTRA_MEM_RATIO * ram_pages;
+
+ /*
+ * Convert UNUSABLE ranges to RAM and reserve them for foreign mapping
+ * purposes.
+ */
+ for (i = 0; i < bootp->e820_entries && extra_pages; i++) {
+ struct boot_e820_entry *e = &bootp->e820_table[i];
+ unsigned long pages;
+
+ if (e->type != E820_TYPE_UNUSABLE)
+ continue;
+
+ pages = min(extra_pages,
+ PFN_DOWN(e->addr + e->size) - PFN_UP(e->addr));
+
+ if (pages != (PFN_DOWN(e->addr + e->size) - PFN_UP(e->addr))) {
+ struct boot_e820_entry *next;
+
+ if (bootp->e820_entries ==
+ ARRAY_SIZE(bootp->e820_table))
+ /* No space left to split - skip region. */
+ continue;
+
+ /* Split entry. */
+ next = e + 1;
+ memmove(next, e,
+ (bootp->e820_entries - i) * sizeof(*e));
+ bootp->e820_entries++;
+ next->addr = PAGE_ALIGN(e->addr) + PFN_PHYS(pages);
+ e->size = next->addr - e->addr;
+ next->size -= e->size;
+ }
+ e->type = E820_TYPE_RAM;
+ extra_pages -= pages;
+
+ xen_add_extra_mem(PFN_UP(e->addr), pages);
+ }
+}
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index b3e37961065a..380591028cb8 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -38,9 +38,6 @@
#define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024)
-/* Amount of extra memory space we add to the e820 ranges */
-struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
-
/* Number of pages released from the initial allocation. */
unsigned long xen_released_pages;
@@ -64,18 +61,6 @@ static struct {
} xen_remap_buf __initdata __aligned(PAGE_SIZE);
static unsigned long xen_remap_mfn __initdata = INVALID_P2M_ENTRY;
-/*
- * The maximum amount of extra memory compared to the base size. The
- * main scaling factor is the size of struct page. At extreme ratios
- * of base:extra, all the base memory can be filled with page
- * structures for the extra memory, leaving no space for anything
- * else.
- *
- * 10x seems like a reasonable balance between scaling flexibility and
- * leaving a practically usable system.
- */
-#define EXTRA_MEM_RATIO (10)
-
static bool xen_512gb_limit __initdata = IS_ENABLED(CONFIG_XEN_512GB);
static void __init xen_parse_512gb(void)
@@ -96,35 +81,6 @@ static void __init xen_parse_512gb(void)
xen_512gb_limit = val;
}
-static void __init xen_add_extra_mem(unsigned long start_pfn,
- unsigned long n_pfns)
-{
- int i;
-
- /*
- * No need to check for zero size, should happen rarely and will only
- * write a new entry regarded to be unused due to zero size.
- */
- for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
- /* Add new region. */
- if (xen_extra_mem[i].n_pfns == 0) {
- xen_extra_mem[i].start_pfn = start_pfn;
- xen_extra_mem[i].n_pfns = n_pfns;
- break;
- }
- /* Append to existing region. */
- if (xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns ==
- start_pfn) {
- xen_extra_mem[i].n_pfns += n_pfns;
- break;
- }
- }
- if (i == XEN_EXTRA_MEM_MAX_REGIONS)
- printk(KERN_WARNING "Warning: not enough extra memory regions\n");
-
- memblock_reserve(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns));
-}
-
static void __init xen_del_extra_mem(unsigned long start_pfn,
unsigned long n_pfns)
{
diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c
index 27d1a5b7f571..ac41d83b38d3 100644
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -154,9 +154,9 @@ static void __init xen_pv_smp_config(void)
u32 apicid = 0;
int i;
- topology_register_boot_apic(apicid++);
+ topology_register_boot_apic(apicid);
- for (i = 1; i < nr_cpu_ids; i++)
+ for (i = 0; i < nr_cpu_ids; i++)
topology_register_apic(apicid++, CPU_ACPIID_INVALID, true);
/* Pretend to be a proper enumerated system */
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index 04101b984f24..758bcd47b72d 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -49,7 +49,7 @@ SYM_CODE_START(startup_xen)
ANNOTATE_NOENDBR
cld
- leaq (__end_init_task - TOP_OF_KERNEL_STACK_PADDING - PTREGS_SIZE)(%rip), %rsp
+ leaq __top_init_kernel_stack(%rip), %rsp
/* Set up %gs.
*
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index a87ab36889e7..79cf93f2c92f 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -163,4 +163,18 @@ void xen_hvm_post_suspend(int suspend_cancelled);
static inline void xen_hvm_post_suspend(int suspend_cancelled) {}
#endif
+/*
+ * The maximum amount of extra memory compared to the base size. The
+ * main scaling factor is the size of struct page. At extreme ratios
+ * of base:extra, all the base memory can be filled with page
+ * structures for the extra memory, leaving no space for anything
+ * else.
+ *
+ * 10x seems like a reasonable balance between scaling flexibility and
+ * leaving a practically usable system.
+ */
+#define EXTRA_MEM_RATIO (10)
+
+void xen_add_extra_mem(unsigned long start_pfn, unsigned long n_pfns);
+
#endif /* XEN_OPS_H */