Merge tag 'for-linus-5.15b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Some minor cleanups and fixes of some theoretical bugs, as well as a
  fix of a bug introduced in 5.15-rc1"

* tag 'for-linus-5.15b-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/x86: fix PV trap handling on secondary processors
  xen/balloon: fix balloon kthread freezing
  swiotlb-xen: this is PV-only on x86
  xen/pci-swiotlb: reduce visibility of symbols
  PCI: only build xen-pcifront in PV-enabled environments
  swiotlb-xen: ensure to issue well-formed XENMEM_exchange requests
  Xen/gntdev: don't ignore kernel unmapping error
  xen/x86: drop redundant zeroing from cpu_initialize_context()

arch/x86/Kconfig

@@ -2610,7 +2610,6 @@ config PCI_OLPC
 config PCI_XEN
 	def_bool y
 	depends on PCI && XEN
-	select SWIOTLB_XEN
 
 config MMCONF_FAM10H
 	def_bool y

arch/x86/include/asm/xen/swiotlb-xen.h

@@ -3,14 +3,10 @@
 #define _ASM_X86_SWIOTLB_XEN_H
 
 #ifdef CONFIG_SWIOTLB_XEN
-extern int xen_swiotlb;
 extern int __init pci_xen_swiotlb_detect(void);
-extern void __init pci_xen_swiotlb_init(void);
 extern int pci_xen_swiotlb_init_late(void);
 #else
-#define xen_swiotlb (0)
-static inline int __init pci_xen_swiotlb_detect(void) { return 0; }
-static inline void __init pci_xen_swiotlb_init(void) { }
+#define pci_xen_swiotlb_detect NULL
 static inline int pci_xen_swiotlb_init_late(void) { return -ENXIO; }
 #endif
 

arch/x86/xen/enlighten_pv.c

@@ -755,8 +755,8 @@ static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
 	preempt_enable();
 }
 
-static void xen_convert_trap_info(const struct desc_ptr *desc,
-				  struct trap_info *traps)
+static unsigned xen_convert_trap_info(const struct desc_ptr *desc,
+				      struct trap_info *traps, bool full)
 {
 	unsigned in, out, count;
 
@@ -766,17 +766,18 @@ static void xen_convert_trap_info(const struct desc_ptr *desc,
 	for (in = out = 0; in < count; in++) {
 		gate_desc *entry = (gate_desc *)(desc->address) + in;
 
-		if (cvt_gate_to_trap(in, entry, &traps[out]))
+		if (cvt_gate_to_trap(in, entry, &traps[out]) || full)
 			out++;
 	}
-	traps[out].address = 0;
+
+	return out;
 }
 
 void xen_copy_trap_info(struct trap_info *traps)
 {
 	const struct desc_ptr *desc = this_cpu_ptr(&idt_desc);
 
-	xen_convert_trap_info(desc, traps);
+	xen_convert_trap_info(desc, traps, true);
 }
 
 /* Load a new IDT into Xen.  In principle this can be per-CPU, so we
@@ -786,6 +787,7 @@ static void xen_load_idt(const struct desc_ptr *desc)
 {
 	static DEFINE_SPINLOCK(lock);
 	static struct trap_info traps[257];
+	unsigned out;
 
 	trace_xen_cpu_load_idt(desc);
 
@@ -793,7 +795,8 @@ static void xen_load_idt(const struct desc_ptr *desc)
 
 	memcpy(this_cpu_ptr(&idt_desc), desc, sizeof(idt_desc));
 
-	xen_convert_trap_info(desc, traps);
+	out = xen_convert_trap_info(desc, traps, false);
+	memset(&traps[out], 0, sizeof(traps[0]));
 
 	xen_mc_flush();
 	if (HYPERVISOR_set_trap_table(traps))

arch/x86/xen/pci-swiotlb-xen.c

@@ -18,7 +18,7 @@
 #endif
 #include <linux/export.h>
 
-int xen_swiotlb __read_mostly;
+static int xen_swiotlb __read_mostly;
 
 /*
  * pci_xen_swiotlb_detect - set xen_swiotlb to 1 if necessary
@@ -56,7 +56,7 @@ int __init pci_xen_swiotlb_detect(void)
 	return xen_swiotlb;
 }
 
-void __init pci_xen_swiotlb_init(void)
+static void __init pci_xen_swiotlb_init(void)
 {
 	if (xen_swiotlb) {
 		xen_swiotlb_init_early();

arch/x86/xen/smp_pv.c

@@ -290,8 +290,6 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 
 	gdt = get_cpu_gdt_rw(cpu);
 
-	memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
-
 	/*
 	 * Bring up the CPU in cpu_bringup_and_idle() with the stack
 	 * pointing just below where pt_regs would be if it were a normal
@@ -308,8 +306,6 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 
 	xen_copy_trap_info(ctxt->trap_ctxt);
 
-	ctxt->ldt_ents = 0;
-
 	BUG_ON((unsigned long)gdt & ~PAGE_MASK);
 
 	gdt_mfn = arbitrary_virt_to_mfn(gdt);

drivers/pci/Kconfig

@@ -110,7 +110,7 @@ config PCI_PF_STUB
 
 config XEN_PCIDEV_FRONTEND
 	tristate "Xen PCI Frontend"
-	depends on X86 && XEN
+	depends on XEN_PV
 	select PCI_XEN
 	select XEN_XENBUS_FRONTEND
 	default y

drivers/xen/Kconfig

@@ -177,6 +177,7 @@ config XEN_GRANT_DMA_ALLOC
 
 config SWIOTLB_XEN
 	def_bool y
+	depends on XEN_PV || ARM || ARM64
 	select DMA_OPS
 	select SWIOTLB
 

drivers/xen/balloon.c

@@ -522,7 +522,7 @@ static int balloon_thread(void *unused)
 			timeout = 3600 * HZ;
 		credit = current_credit();
 
-		wait_event_interruptible_timeout(balloon_thread_wq,
+		wait_event_freezable_timeout(balloon_thread_wq,
 			balloon_thread_cond(state, credit), timeout);
 
 		if (kthread_should_stop())

drivers/xen/gntdev.c

@@ -381,6 +381,14 @@ static int __unmap_grant_pages(struct gntdev_grant_map *map, int offset,
 			map->unmap_ops[offset+i].handle,
 			map->unmap_ops[offset+i].status);
 		map->unmap_ops[offset+i].handle = INVALID_GRANT_HANDLE;
+		if (use_ptemod) {
+			if (map->kunmap_ops[offset+i].status)
+				err = -EINVAL;
+			pr_debug("kunmap handle=%u st=%d\n",
+				 map->kunmap_ops[offset+i].handle,
+				 map->kunmap_ops[offset+i].status);
+			map->kunmap_ops[offset+i].handle = INVALID_GRANT_HANDLE;
+		}
 	}
 	return err;
 }

drivers/xen/swiotlb-xen.c

@@ -230,10 +230,11 @@ void __init xen_swiotlb_init_early(void)
 	/*
 	 * Get IO TLB memory from any location.
 	 */
-	start = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE);
+	start = memblock_alloc(PAGE_ALIGN(bytes),
+			       IO_TLB_SEGSIZE << IO_TLB_SHIFT);
 	if (!start)
-		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
-		      __func__, PAGE_ALIGN(bytes), PAGE_SIZE);
+		panic("%s: Failed to allocate %lu bytes\n",
+		      __func__, PAGE_ALIGN(bytes));
 
 	/*
 	 * And replace that memory with pages under 4GB.

include/xen/xen-ops.h

@@ -46,19 +46,7 @@ extern unsigned long *xen_contiguous_bitmap;
 int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order,
 				unsigned int address_bits,
 				dma_addr_t *dma_handle);
-
 void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order);
-#else
-static inline int xen_create_contiguous_region(phys_addr_t pstart,
-					       unsigned int order,
-					       unsigned int address_bits,
-					       dma_addr_t *dma_handle)
-{
-	return 0;
-}
-
-static inline void xen_destroy_contiguous_region(phys_addr_t pstart,
-						 unsigned int order) { }
 #endif
 
 #if defined(CONFIG_XEN_PV)