Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "Several boot fixes (MacBook, legacy EFI bootloaders), another
  please-don't-brick fix, and some minor stuff."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Do not try to sync identity map for non-mapped pages
  x86, doc: Be explicit about what the x86 struct boot_params requires
  x86: Don't clear efi_info even if the sentinel hits
  x86, mm: Make sure to find a 2M free block for the first mapped area
  x86: Fix 32-bit *_cpu_data initializers
  efivarfs: return accurate error code in efivarfs_fill_super()
  efivars: efivarfs_valid_name() should handle pstore syntax
  efi: be more paranoid about available space when creating variables
  iommu, x86: Add DMA remap fault reason
  x86, smpboot: Remove unused variable

8 files changed, 192 insertions, 43 deletions

diff --git a/arch/x86/include/asm/bootparam_utils.h b/arch/x86/include/asm/bootparam_utils.h
index 5b5e9cb774b5..653668d140f9 100644
--- a/arch/x86/include/asm/bootparam_utils.h
+++ b/arch/x86/include/asm/bootparam_utils.h
@@ -14,13 +14,29 @@
  * analysis of kexec-tools; if other broken bootloaders initialize a
  * different set of fields we will need to figure out how to disambiguate.
  *
+ * Note: efi_info is commonly left uninitialized, but that field has a
+ * private magic, so it is better to leave it unchanged.
  */
 static void sanitize_boot_params(struct boot_params *boot_params)
 {
+        /* 
+         * IMPORTANT NOTE TO BOOTLOADER AUTHORS: do not simply clear
+         * this field.  The purpose of this field is to guarantee
+         * compliance with the x86 boot spec located in
+         * Documentation/x86/boot.txt .  That spec says that the
+         * *whole* structure should be cleared, after which only the
+         * portion defined by struct setup_header (boot_params->hdr)
+         * should be copied in.
+         *
+         * If you're having an issue because the sentinel is set, you
+         * need to change the whole structure to be cleared, not this
+         * (or any other) individual field, or you will soon have
+         * problems again.
+         */
         if (boot_params->sentinel) {
-                /*fields in boot_params are not valid, clear them */
+                /* fields in boot_params are left uninitialized, clear them */
                 memset(&boot_params->olpc_ofw_header, 0,
-                       (char *)&boot_params->alt_mem_k -
+                       (char *)&boot_params->efi_info -
                         (char *)&boot_params->olpc_ofw_header);
                 memset(&boot_params->kbd_status, 0,
                        (char *)&boot_params->hdr -
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 84d32855f65c..90d8cc930f5e 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -171,9 +171,15 @@ static struct resource bss_resource = {
 
 #ifdef CONFIG_X86_32
 /* cpu data as detected by the assembly code in head.S */
-struct cpuinfo_x86 new_cpu_data __cpuinitdata = {0, 0, 0, 0, -1, 1, 0, 0, -1};
+struct cpuinfo_x86 new_cpu_data __cpuinitdata = {
+        .wp_works_ok = -1,
+        .fdiv_bug = -1,
+};
 /* common cpu data for all cpus */
-struct cpuinfo_x86 boot_cpu_data __read_mostly = {0, 0, 0, 0, -1, 1, 0, 0, -1};
+struct cpuinfo_x86 boot_cpu_data __read_mostly = {
+        .wp_works_ok = -1,
+        .fdiv_bug = -1,
+};
 EXPORT_SYMBOL(boot_cpu_data);
 
 unsigned int def_to_bigsmp;
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index a6ceaedc396a..9f190a2a00e9 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1365,9 +1365,8 @@ static inline void mwait_play_dead(void)
         unsigned int eax, ebx, ecx, edx;
         unsigned int highest_cstate = 0;
         unsigned int highest_subcstate = 0;
-        int i;
         void *mwait_ptr;
-        struct cpuinfo_x86 *c = __this_cpu_ptr(&cpu_info);
+        int i;
 
         if (!this_cpu_has(X86_FEATURE_MWAIT))
                 return;
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 4903a03ae876..59b7fc453277 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -410,9 +410,8 @@ void __init init_mem_mapping(void)
         /* the ISA range is always mapped regardless of memory holes */
         init_memory_mapping(0, ISA_END_ADDRESS);
 
-        /* xen has big range in reserved near end of ram, skip it at first */
-        addr = memblock_find_in_range(ISA_END_ADDRESS, end, PMD_SIZE,
-                         PAGE_SIZE);
+        /* xen has big range in reserved near end of ram, skip it at first.*/
+        addr = memblock_find_in_range(ISA_END_ADDRESS, end, PMD_SIZE, PMD_SIZE);
         real_end = addr + PMD_SIZE;
 
         /* step_size need to be small so pgt_buf from BRK could cover it */
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 2610bd93c896..657438858e83 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -563,6 +563,13 @@ int kernel_map_sync_memtype(u64 base, unsigned long size, unsigned long flags)
         if (base > __pa(high_memory-1))
                 return 0;
 
+        /*
+         * some areas in the middle of the kernel identity range
+         * are not mapped, like the PCI space.
+         */
+        if (!page_is_ram(base >> PAGE_SHIFT))
+                return 0;
+
         id_sz = (__pa(high_memory-1) <= base + size) ?
                                 __pa(high_memory) - base :
                                 size;
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 7320bf891706..bea32d1ef7d5 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -426,6 +426,44 @@ get_var_data(struct efivars *efivars, struct efi_variable *var)
         return status;
 }
 
+static efi_status_t
+check_var_size_locked(struct efivars *efivars, u32 attributes,
+                        unsigned long size)
+{
+        u64 storage_size, remaining_size, max_size;
+        efi_status_t status;
+        const struct efivar_operations *fops = efivars->ops;
+
+        if (!efivars->ops->query_variable_info)
+                return EFI_UNSUPPORTED;
+
+        status = fops->query_variable_info(attributes, &storage_size,
+                                           &remaining_size, &max_size);
+
+        if (status != EFI_SUCCESS)
+                return status;
+
+        if (!storage_size || size > remaining_size || size > max_size ||
+            (remaining_size - size) < (storage_size / 2))
+                return EFI_OUT_OF_RESOURCES;
+
+        return status;
+}
+
+
+static efi_status_t
+check_var_size(struct efivars *efivars, u32 attributes, unsigned long size)
+{
+        efi_status_t status;
+        unsigned long flags;
+
+        spin_lock_irqsave(&efivars->lock, flags);
+        status = check_var_size_locked(efivars, attributes, size);
+        spin_unlock_irqrestore(&efivars->lock, flags);
+
+        return status;
+}
+
 static ssize_t
 efivar_guid_read(struct efivar_entry *entry, char *buf)
 {
@@ -547,11 +585,16 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
         }
 
         spin_lock_irq(&efivars->lock);
-        status = efivars->ops->set_variable(new_var->VariableName,
-                                            &new_var->VendorGuid,
-                                            new_var->Attributes,
-                                            new_var->DataSize,
-                                            new_var->Data);
+
+        status = check_var_size_locked(efivars, new_var->Attributes,
+               new_var->DataSize + utf16_strsize(new_var->VariableName, 1024));
+
+        if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED)
+                status = efivars->ops->set_variable(new_var->VariableName,
+                                                    &new_var->VendorGuid,
+                                                    new_var->Attributes,
+                                                    new_var->DataSize,
+                                                    new_var->Data);
 
         spin_unlock_irq(&efivars->lock);
 
@@ -702,8 +745,7 @@ static ssize_t efivarfs_file_write(struct file *file,
         u32 attributes;
         struct inode *inode = file->f_mapping->host;
         unsigned long datasize = count - sizeof(attributes);
-        unsigned long newdatasize;
-        u64 storage_size, remaining_size, max_size;
+        unsigned long newdatasize, varsize;
         ssize_t bytes = 0;
 
         if (count < sizeof(attributes))
@@ -722,28 +764,18 @@ static ssize_t efivarfs_file_write(struct file *file,
          * amounts of memory. Pick a default size of 64K if
          * QueryVariableInfo() isn't supported by the firmware.
          */
-        spin_lock_irq(&efivars->lock);
-
-        if (!efivars->ops->query_variable_info)
-                status = EFI_UNSUPPORTED;
-        else {
-                const struct efivar_operations *fops = efivars->ops;
-                status = fops->query_variable_info(attributes, &storage_size,
-                                                   &remaining_size, &max_size);
-        }
 
-        spin_unlock_irq(&efivars->lock);
+        varsize = datasize + utf16_strsize(var->var.VariableName, 1024);
+        status = check_var_size(efivars, attributes, varsize);
 
         if (status != EFI_SUCCESS) {
                 if (status != EFI_UNSUPPORTED)
                         return efi_status_to_err(status);
 
-                remaining_size = 65536;
+                if (datasize > 65536)
+                        return -ENOSPC;
         }
 
-        if (datasize > remaining_size)
-                return -ENOSPC;
-
         data = kmalloc(datasize, GFP_KERNEL);
         if (!data)
                 return -ENOMEM;
@@ -765,6 +797,19 @@ static ssize_t efivarfs_file_write(struct file *file,
          */
         spin_lock_irq(&efivars->lock);
 
+        /*
+         * Ensure that the available space hasn't shrunk below the safe level
+         */
+
+        status = check_var_size_locked(efivars, attributes, varsize);
+
+        if (status != EFI_SUCCESS && status != EFI_UNSUPPORTED) {
+                spin_unlock_irq(&efivars->lock);
+                kfree(data);
+
+                return efi_status_to_err(status);
+        }
+
         status = efivars->ops->set_variable(var->var.VariableName,
                                             &var->var.VendorGuid,
                                             attributes, datasize,
@@ -929,8 +974,8 @@ static bool efivarfs_valid_name(const char *str, int len)
         if (len < GUID_LEN + 2)
                 return false;
 
-        /* GUID should be right after the first '-' */
-        if (s - 1 != strchr(str, '-'))
+        /* GUID must be preceded by a '-' */
+        if (*(s - 1) != '-')
                 return false;
 
         /*
@@ -1118,15 +1163,22 @@ static struct dentry_operations efivarfs_d_ops = {
 
 static struct dentry *efivarfs_alloc_dentry(struct dentry *parent, char *name)
 {
+        struct dentry *d;
         struct qstr q;
+        int err;
 
         q.name = name;
         q.len = strlen(name);
 
-        if (efivarfs_d_hash(NULL, NULL, &q))
-                return NULL;
+        err = efivarfs_d_hash(NULL, NULL, &q);
+        if (err)
+                return ERR_PTR(err);
+
+        d = d_alloc(parent, &q);
+        if (d)
+                return d;
 
-        return d_alloc(parent, &q);
+        return ERR_PTR(-ENOMEM);
 }
 
 static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
@@ -1136,6 +1188,7 @@ static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
         struct efivar_entry *entry, *n;
         struct efivars *efivars = &__efivars;
         char *name;
+        int err = -ENOMEM;
 
         efivarfs_sb = sb;
 
@@ -1186,8 +1239,10 @@ static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
                         goto fail_name;
 
                 dentry = efivarfs_alloc_dentry(root, name);
-                if (!dentry)
+                if (IS_ERR(dentry)) {
+                        err = PTR_ERR(dentry);
                         goto fail_inode;
+                }
 
                 /* copied by the above to local storage in the dentry. */
                 kfree(name);
@@ -1214,7 +1269,7 @@ fail_inode:
 fail_name:
         kfree(name);
 fail:
-        return -ENOMEM;
+        return err;
 }
 
 static struct dentry *efivarfs_mount(struct file_system_type *fs_type,
@@ -1345,7 +1400,6 @@ static int efi_pstore_write(enum pstore_type_id type,
         efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
         struct efivars *efivars = psi->data;
         int i, ret = 0;
-        u64 storage_space, remaining_space, max_variable_size;
         efi_status_t status = EFI_NOT_FOUND;
         unsigned long flags;
 
@@ -1365,11 +1419,11 @@ static int efi_pstore_write(enum pstore_type_id type,
          * size: a size of logging data
          * DUMP_NAME_LEN * 2: a maximum size of variable name
          */
-        status = efivars->ops->query_variable_info(PSTORE_EFI_ATTRIBUTES,
-                                                   &storage_space,
-                                                   &remaining_space,
-                                                   &max_variable_size);
-        if (status || remaining_space < size + DUMP_NAME_LEN * 2) {
+
+        status = check_var_size_locked(efivars, PSTORE_EFI_ATTRIBUTES,
+                                         size + DUMP_NAME_LEN * 2);
+
+        if (status) {
                 spin_unlock_irqrestore(&efivars->lock, flags);
                 *id = part;
                 return -ENOSPC;
@@ -1544,6 +1598,14 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
                 return -EINVAL;
         }
 
+        status = check_var_size_locked(efivars, new_var->Attributes,
+               new_var->DataSize + utf16_strsize(new_var->VariableName, 1024));
+
+        if (status && status != EFI_UNSUPPORTED) {
+                spin_unlock_irq(&efivars->lock);
+                return efi_status_to_err(status);
+        }
+
         /* now *really* create the variable via EFI */
         status = efivars->ops->set_variable(new_var->VariableName,
                                             &new_var->VendorGuid,
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index dc7e478b7e5f..e5cdaf87822c 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1083,6 +1083,7 @@ static const char *dma_remap_fault_reasons[] =
         "non-zero reserved fields in RTP",
         "non-zero reserved fields in CTP",
         "non-zero reserved fields in PTE",
+        "PCE for translation request specifies blocking",
 };
 
 static const char *irq_remap_fault_reasons[] =
diff --git a/tools/testing/selftests/efivarfs/efivarfs.sh b/tools/testing/selftests/efivarfs/efivarfs.sh
index 880cdd5dc63f..77edcdcc016b 100644
--- a/tools/testing/selftests/efivarfs/efivarfs.sh
+++ b/tools/testing/selftests/efivarfs/efivarfs.sh
@@ -125,6 +125,63 @@ test_open_unlink()
         ./open-unlink $file
 }
 
+# test that we can create a range of filenames
+test_valid_filenames()
+{
+        local attrs='\x07\x00\x00\x00'
+        local ret=0
+
+        local file_list="abc dump-type0-11-1-1362436005 1234 -"
+        for f in $file_list; do
+                local file=$efivarfs_mount/$f-$test_guid
+
+                printf "$attrs\x00" > $file
+
+                if [ ! -e $file ]; then
+                        echo "$file could not be created" >&2
+                        ret=1
+                else
+                        rm $file
+                fi
+        done
+
+        exit $ret
+}
+
+test_invalid_filenames()
+{
+        local attrs='\x07\x00\x00\x00'
+        local ret=0
+
+        local file_list="
+                -1234-1234-1234-123456789abc
+                foo
+                foo-bar
+                -foo-
+                foo-barbazba-foob-foob-foob-foobarbazfoo
+                foo-------------------------------------
+                -12345678-1234-1234-1234-123456789abc
+                a-12345678=1234-1234-1234-123456789abc
+                a-12345678-1234=1234-1234-123456789abc
+                a-12345678-1234-1234=1234-123456789abc
+                a-12345678-1234-1234-1234=123456789abc
+                1112345678-1234-1234-1234-123456789abc"
+
+        for f in $file_list; do
+                local file=$efivarfs_mount/$f
+
+                printf "$attrs\x00" 2>/dev/null > $file
+
+                if [ -e $file ]; then
+                        echo "Creating $file should have failed" >&2
+                        rm $file
+                        ret=1
+                fi
+        done
+
+        exit $ret
+}
+
 check_prereqs
 
 rc=0
@@ -135,5 +192,7 @@ run_test test_create_read
 run_test test_delete
 run_test test_zero_size_delete
 run_test test_open_unlink
+run_test test_valid_filenames
+run_test test_invalid_filenames
 
 exit $rc