Merge tag 'x86-cleanups-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups & removal of obsolete code"

* tag 'x86-cleanups-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sgx: Correct kernel-doc's arg name in sgx_encl_release()
  doc: Remove references to IBM Calgary
  x86/setup: Document that Windows reserves the first MiB
  x86/crash: Remove crash_reserve_low_1M()
  x86/setup: Remove CONFIG_X86_RESERVE_LOW and reservelow= options
  x86/alternative: Align insn bytes vertically
  x86: Fix leftover comment typos
  x86/asm: Simplify __smp_mb() definition
  x86/alternatives: Make the x86nops[] symbol static

Documentation/admin-guide/kernel-parameters.txt

@@ -4775,11 +4775,6 @@
 			Reserves a hole at the top of the kernel virtual
 			address space.
 
-	reservelow=	[X86]
-			Format: nn[K]
-			Set the amount of memory to reserve for BIOS at
-			the bottom of the address space.
-
 	reset_devices	[KNL] Force drivers to reset the underlying device
 			during initialization.
 

Documentation/x86/x86_64/boot-options.rst

@@ -247,16 +247,11 @@ Multiple x86-64 PCI-DMA mapping implementations exist, for example:
       Kernel boot message: "PCI-DMA: Using software bounce buffering
       for IO (SWIOTLB)"
 
-   4. <arch/x86_64/pci-calgary.c> : IBM Calgary hardware IOMMU. Used in IBM
-      pSeries and xSeries servers. This hardware IOMMU supports DMA address
-      mapping with memory protection, etc.
-      Kernel boot message: "PCI-DMA: Using Calgary IOMMU"
-
 ::
 
   iommu=[<size>][,noagp][,off][,force][,noforce]
   [,memaper[=<order>]][,merge][,fullflush][,nomerge]
-  [,noaperture][,calgary]
+  [,noaperture]
 
 General iommu options:
 
@@ -295,8 +290,6 @@ iommu options only relevant to the AMD GART hardware IOMMU:
       Don't initialize the AGP driver and use full aperture.
     panic
       Always panic when IOMMU overflows.
-    calgary
-      Use the Calgary IOMMU if it is available
 
 iommu options only relevant to the software bounce buffering (SWIOTLB) IOMMU
 implementation:
@@ -307,28 +300,6 @@ implementation:
       force
         Force all IO through the software TLB.
 
-Settings for the IBM Calgary hardware IOMMU currently found in IBM
-pSeries and xSeries machines
-
-    calgary=[64k,128k,256k,512k,1M,2M,4M,8M]
-      Set the size of each PCI slot's translation table when using the
-      Calgary IOMMU. This is the size of the translation table itself
-      in main memory. The smallest table, 64k, covers an IO space of
-      32MB; the largest, 8MB table, can cover an IO space of 4GB.
-      Normally the kernel will make the right choice by itself.
-    calgary=[translate_empty_slots]
-      Enable translation even on slots that have no devices attached to
-      them, in case a device will be hotplugged in the future.
-    calgary=[disable=<PCI bus number>]
-      Disable translation on a given PHB. For
-      example, the built-in graphics adapter resides on the first bridge
-      (PCI bus number 0); if translation (isolation) is enabled on this
-      bridge, X servers that access the hardware directly from user
-      space might stop working. Use this option if you have devices that
-      are accessed from userspace directly on some PCI host bridge.
-    panic
-      Always panic when IOMMU overflows
-
 
 Miscellaneous
 =============

arch/x86/Kconfig

@@ -1693,35 +1693,6 @@ config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
 	  Set whether the default state of memory_corruption_check is
 	  on or off.
 
-config X86_RESERVE_LOW
-	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
-	default 64
-	range 4 640
-	help
-	  Specify the amount of low memory to reserve for the BIOS.
-
-	  The first page contains BIOS data structures that the kernel
-	  must not use, so that page must always be reserved.
-
-	  By default we reserve the first 64K of physical RAM, as a
-	  number of BIOSes are known to corrupt that memory range
-	  during events such as suspend/resume or monitor cable
-	  insertion, so it must not be used by the kernel.
-
-	  You can set this to 4 if you are absolutely sure that you
-	  trust the BIOS to get all its memory reservations and usages
-	  right.  If you know your BIOS have problems beyond the
-	  default 64K area, you can set this to 640 to avoid using the
-	  entire low memory range.
-
-	  If you have doubts about the BIOS (e.g. suspend/resume does
-	  not work or there's kernel crashes after certain hardware
-	  hotplug events) then you might want to enable
-	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
-	  typical corruption patterns.
-
-	  Leave this to the default value of 64 if you are unsure.
-
 config MATH_EMULATION
 	bool
 	depends on MODIFY_LDT_SYSCALL

arch/x86/hyperv/hv_init.c

@@ -623,7 +623,7 @@ bool hv_query_ext_cap(u64 cap_query)
 	 * output parameter to the hypercall below and so it should be
 	 * compatible with 'virt_to_phys'. Which means, it's address should be
 	 * directly mapped. Use 'static' to keep it compatible; stack variables
-	 * can be virtually mapped, making them imcompatible with
+	 * can be virtually mapped, making them incompatible with
 	 * 'virt_to_phys'.
 	 * Hypercall input/output addresses should also be 8-byte aligned.
 	 */

arch/x86/include/asm/barrier.h

@@ -54,11 +54,8 @@ static inline unsigned long array_index_mask_nospec(unsigned long index,
 #define dma_rmb()	barrier()
 #define dma_wmb()	barrier()
 
-#ifdef CONFIG_X86_32
-#define __smp_mb()	asm volatile("lock; addl $0,-4(%%esp)" ::: "memory", "cc")
-#else
-#define __smp_mb()	asm volatile("lock; addl $0,-4(%%rsp)" ::: "memory", "cc")
-#endif
+#define __smp_mb()	asm volatile("lock; addl $0,-4(%%" _ASM_SP ")" ::: "memory", "cc")
+
 #define __smp_rmb()	dma_rmb()
 #define __smp_wmb()	barrier()
 #define __smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)

arch/x86/include/asm/crash.h

@@ -9,10 +9,4 @@ int crash_setup_memmap_entries(struct kimage *image,
 		struct boot_params *params);
 void crash_smp_send_stop(void);
 
-#ifdef CONFIG_KEXEC_CORE
-void __init crash_reserve_low_1M(void);
-#else
-static inline void __init crash_reserve_low_1M(void) { }
-#endif
-
 #endif /* _ASM_X86_CRASH_H */

arch/x86/include/asm/sgx.h

@@ -13,7 +13,7 @@
 /*
  * This file contains both data structures defined by SGX architecture and Linux
  * defined software data structures and functions.  The two should not be mixed
- * together for better readibility.  The architectural definitions come first.
+ * together for better readability.  The architectural definitions come first.
  */
 
 /* The SGX specific CPUID function. */

arch/x86/include/asm/stackprotector.h

@@ -11,7 +11,7 @@
  * The same segment is shared by percpu area and stack canary.  On
  * x86_64, percpu symbols are zero based and %gs (64-bit) points to the
  * base of percpu area.  The first occupant of the percpu area is always
- * fixed_percpu_data which contains stack_canary at the approproate
+ * fixed_percpu_data which contains stack_canary at the appropriate
  * offset.  On x86_32, the stack canary is just a regular percpu
  * variable.
  *

arch/x86/kernel/alternative.c

@@ -75,7 +75,7 @@ do {									\
 	}								\
 } while (0)
 
-const unsigned char x86nops[] =
+static const unsigned char x86nops[] =
 {
 	BYTES_NOP1,
 	BYTES_NOP2,

arch/x86/kernel/cpu/sgx/encl.c

@@ -383,7 +383,7 @@ const struct vm_operations_struct sgx_vm_ops = {
 
 /**
  * sgx_encl_release - Destroy an enclave instance
- * @kref:	address of a kref inside &sgx_encl
+ * @ref:	address of a kref inside &sgx_encl
  *
  * Used together with kref_put(). Frees all the resources associated with the
  * enclave and the instance itself.

arch/x86/kernel/crash.c

@@ -70,19 +70,6 @@ static inline void cpu_crash_vmclear_loaded_vmcss(void)
 	rcu_read_unlock();
 }
 
-/*
- * When the crashkernel option is specified, only use the low
- * 1M for the real mode trampoline.
- */
-void __init crash_reserve_low_1M(void)
-{
-	if (cmdline_find_option(boot_command_line, "crashkernel", NULL, 0) < 0)
-		return;
-
-	memblock_reserve(0, 1<<20);
-	pr_info("Reserving the low 1M of memory for crashkernel\n");
-}
-
 #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
 
 static void kdump_nmi_callback(int cpu, struct pt_regs *regs)

arch/x86/kernel/kprobes/core.c

@@ -674,7 +674,7 @@ static int prepare_emulation(struct kprobe *p, struct insn *insn)
 			break;
 
 		if (insn->addr_bytes != sizeof(unsigned long))
-			return -EOPNOTSUPP;	/* Don't support differnt size */
+			return -EOPNOTSUPP;	/* Don't support different size */
 		if (X86_MODRM_MOD(opcode) != 3)
 			return -EOPNOTSUPP;	/* TODO: support memory addressing */
 

arch/x86/kernel/setup.c

@@ -695,30 +695,6 @@ static void __init e820_add_kernel_range(void)
 	e820__range_add(start, size, E820_TYPE_RAM);
 }
 
-static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10;
-
-static int __init parse_reservelow(char *p)
-{
-	unsigned long long size;
-
-	if (!p)
-		return -EINVAL;
-
-	size = memparse(p, &p);
-
-	if (size < 4096)
-		size = 4096;
-
-	if (size > 640*1024)
-		size = 640*1024;
-
-	reserve_low = size;
-
-	return 0;
-}
-
-early_param("reservelow", parse_reservelow);
-
 static void __init early_reserve_memory(void)
 {
 	/*
@@ -1084,17 +1060,18 @@ void __init setup_arch(char **cmdline_p)
 #endif
 
 	/*
-	 * Find free memory for the real mode trampoline and place it
-	 * there.
-	 * If there is not enough free memory under 1M, on EFI-enabled
-	 * systems there will be additional attempt to reclaim the memory
-	 * for the real mode trampoline at efi_free_boot_services().
+	 * Find free memory for the real mode trampoline and place it there. If
+	 * there is not enough free memory under 1M, on EFI-enabled systems
+	 * there will be additional attempt to reclaim the memory for the real
+	 * mode trampoline at efi_free_boot_services().
+	 *
+	 * Unconditionally reserve the entire first 1M of RAM because BIOSes
+	 * are known to corrupt low memory and several hundred kilobytes are not
+	 * worth complex detection what memory gets clobbered. Windows does the
+	 * same thing for very similar reasons.
 	 *
-	 * Unconditionally reserve the entire first 1M of RAM because
-	 * BIOSes are know to corrupt low memory and several
-	 * hundred kilobytes are not worth complex detection what memory gets
-	 * clobbered. Moreover, on machines with SandyBridge graphics or in
-	 * setups that use crashkernel the entire 1M is reserved anyway.
+	 * Moreover, on machines with SandyBridge graphics or in setups that use
+	 * crashkernel the entire 1M is reserved anyway.
 	 */
 	reserve_real_mode();
 

arch/x86/kvm/mmu/mmu.c

@@ -2374,7 +2374,7 @@ static int make_mmu_pages_available(struct kvm_vcpu *vcpu)
 	 * page is available, while the caller may end up allocating as many as
 	 * four pages, e.g. for PAE roots or for 5-level paging.  Temporarily
 	 * exceeding the (arbitrary by default) limit will not harm the host,
-	 * being too agressive may unnecessarily kill the guest, and getting an
+	 * being too aggressive may unnecessarily kill the guest, and getting an
 	 * exact count is far more trouble than it's worth, especially in the
 	 * page fault paths.
 	 */

arch/x86/kvm/mmu/tdp_mmu.c

@@ -1017,7 +1017,7 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
 
 		if (!is_shadow_present_pte(iter.old_spte)) {
 			/*
-			 * If SPTE has been forzen by another thread, just
+			 * If SPTE has been frozen by another thread, just
 			 * give up and retry, avoiding unnecessary page table
 			 * allocation and free.
 			 */