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-rw-r--r--kernel/dma/contiguous.c56
-rw-r--r--kernel/dma/direct.c55
-rw-r--r--kernel/dma/mapping.c12
-rw-r--r--kernel/dma/remap.c16
-rw-r--r--kernel/dma/swiotlb.c25
-rw-r--r--kernel/fail_function.c23
-rw-r--r--kernel/gcov/fs.c24
-rwxr-xr-xkernel/gen_kheaders.sh51
-rw-r--r--kernel/iomem.c2
-rw-r--r--kernel/kprobes.c25
-rw-r--r--kernel/livepatch/transition.c11
-rw-r--r--kernel/stacktrace.c10
-rw-r--r--kernel/time/vsyscall.c6
-rw-r--r--kernel/trace/blktrace.c6
-rw-r--r--kernel/trace/trace.c4
15 files changed, 152 insertions, 174 deletions
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index b2a87905846d..bfc0c17f2a3d 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -214,6 +214,62 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
return cma_release(dev_get_cma_area(dev), pages, count);
}
+/**
+ * dma_alloc_contiguous() - allocate contiguous pages
+ * @dev: Pointer to device for which the allocation is performed.
+ * @size: Requested allocation size.
+ * @gfp: Allocation flags.
+ *
+ * This function allocates contiguous memory buffer for specified device. It
+ * first tries to use device specific contiguous memory area if available or
+ * the default global one, then tries a fallback allocation of normal pages.
+ *
+ * Note that it byapss one-page size of allocations from the global area as
+ * the addresses within one page are always contiguous, so there is no need
+ * to waste CMA pages for that kind; it also helps reduce fragmentations.
+ */
+struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp)
+{
+ int node = dev ? dev_to_node(dev) : NUMA_NO_NODE;
+ size_t count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ size_t align = get_order(PAGE_ALIGN(size));
+ struct page *page = NULL;
+ struct cma *cma = NULL;
+
+ if (dev && dev->cma_area)
+ cma = dev->cma_area;
+ else if (count > 1)
+ cma = dma_contiguous_default_area;
+
+ /* CMA can be used only in the context which permits sleeping */
+ if (cma && gfpflags_allow_blocking(gfp)) {
+ align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT);
+ page = cma_alloc(cma, count, align, gfp & __GFP_NOWARN);
+ }
+
+ /* Fallback allocation of normal pages */
+ if (!page)
+ page = alloc_pages_node(node, gfp, align);
+ return page;
+}
+
+/**
+ * dma_free_contiguous() - release allocated pages
+ * @dev: Pointer to device for which the pages were allocated.
+ * @page: Pointer to the allocated pages.
+ * @size: Size of allocated pages.
+ *
+ * This function releases memory allocated by dma_alloc_contiguous(). As the
+ * cma_release returns false when provided pages do not belong to contiguous
+ * area and true otherwise, this function then does a fallback __free_pages()
+ * upon a false-return.
+ */
+void dma_free_contiguous(struct device *dev, struct page *page, size_t size)
+{
+ if (!cma_release(dev_get_cma_area(dev), page, size >> PAGE_SHIFT))
+ __free_pages(page, get_order(size));
+}
+
/*
* Support for reserved memory regions defined in device tree
*/
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 2c2772e9702a..b90e1aede743 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -96,8 +96,6 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
- unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
- int page_order = get_order(size);
struct page *page = NULL;
u64 phys_mask;
@@ -109,20 +107,9 @@ struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp |= __dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
&phys_mask);
again:
- /* CMA can be used only in the context which permits sleeping */
- if (gfpflags_allow_blocking(gfp)) {
- page = dma_alloc_from_contiguous(dev, count, page_order,
- gfp & __GFP_NOWARN);
- if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
- dma_release_from_contiguous(dev, page, count);
- page = NULL;
- }
- }
- if (!page)
- page = alloc_pages_node(dev_to_node(dev), gfp, page_order);
-
+ page = dma_alloc_contiguous(dev, size, gfp);
if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
- __free_pages(page, page_order);
+ dma_free_contiguous(dev, page, size);
page = NULL;
if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
@@ -151,10 +138,18 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
if (!page)
return NULL;
+ if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
+ /* remove any dirty cache lines on the kernel alias */
+ if (!PageHighMem(page))
+ arch_dma_prep_coherent(page, size);
+ /* return the page pointer as the opaque cookie */
+ return page;
+ }
+
if (PageHighMem(page)) {
/*
* Depending on the cma= arguments and per-arch setup
- * dma_alloc_from_contiguous could return highmem pages.
+ * dma_alloc_contiguous could return highmem pages.
* Without remapping there is no way to return them here,
* so log an error and fail.
*/
@@ -171,15 +166,19 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
*dma_handle = phys_to_dma(dev, page_to_phys(page));
}
memset(ret, 0, size);
+
+ if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ dma_alloc_need_uncached(dev, attrs)) {
+ arch_dma_prep_coherent(page, size);
+ ret = uncached_kernel_address(ret);
+ }
+
return ret;
}
void __dma_direct_free_pages(struct device *dev, size_t size, struct page *page)
{
- unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-
- if (!dma_release_from_contiguous(dev, page, count))
- __free_pages(page, get_order(size));
+ dma_free_contiguous(dev, page, size);
}
void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
@@ -187,15 +186,26 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
{
unsigned int page_order = get_order(size);
+ if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
+ /* cpu_addr is a struct page cookie, not a kernel address */
+ __dma_direct_free_pages(dev, size, cpu_addr);
+ return;
+ }
+
if (force_dma_unencrypted())
set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order);
+
+ if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ dma_alloc_need_uncached(dev, attrs))
+ cpu_addr = cached_kernel_address(cpu_addr);
__dma_direct_free_pages(dev, size, virt_to_page(cpu_addr));
}
void *dma_direct_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
- if (!dev_is_dma_coherent(dev))
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ dma_alloc_need_uncached(dev, attrs))
return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
}
@@ -203,7 +213,8 @@ void *dma_direct_alloc(struct device *dev, size_t size,
void dma_direct_free(struct device *dev, size_t size,
void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs)
{
- if (!dev_is_dma_coherent(dev))
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ dma_alloc_need_uncached(dev, attrs))
arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
else
dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs);
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index f7afdadb6770..1f628e7ac709 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -317,6 +317,12 @@ void arch_dma_set_mask(struct device *dev, u64 mask);
int dma_set_mask(struct device *dev, u64 mask)
{
+ /*
+ * Truncate the mask to the actually supported dma_addr_t width to
+ * avoid generating unsupportable addresses.
+ */
+ mask = (dma_addr_t)mask;
+
if (!dev->dma_mask || !dma_supported(dev, mask))
return -EIO;
@@ -330,6 +336,12 @@ EXPORT_SYMBOL(dma_set_mask);
#ifndef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK
int dma_set_coherent_mask(struct device *dev, u64 mask)
{
+ /*
+ * Truncate the mask to the actually supported dma_addr_t width to
+ * avoid generating unsupportable addresses.
+ */
+ mask = (dma_addr_t)mask;
+
if (!dma_supported(dev, mask))
return -EIO;
diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c
index 7a723194ecbe..a594aec07882 100644
--- a/kernel/dma/remap.c
+++ b/kernel/dma/remap.c
@@ -158,6 +158,9 @@ out:
bool dma_in_atomic_pool(void *start, size_t size)
{
+ if (unlikely(!atomic_pool))
+ return false;
+
return addr_in_gen_pool(atomic_pool, (unsigned long)start, size);
}
@@ -199,8 +202,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
size = PAGE_ALIGN(size);
- if (!gfpflags_allow_blocking(flags) &&
- !(attrs & DMA_ATTR_NO_KERNEL_MAPPING)) {
+ if (!gfpflags_allow_blocking(flags)) {
ret = dma_alloc_from_pool(size, &page, flags);
if (!ret)
return NULL;
@@ -214,11 +216,6 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
/* remove any dirty cache lines on the kernel alias */
arch_dma_prep_coherent(page, size);
- if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
- ret = page; /* opaque cookie */
- goto done;
- }
-
/* create a coherent mapping */
ret = dma_common_contiguous_remap(page, size, VM_USERMAP,
arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs),
@@ -237,10 +234,7 @@ done:
void arch_dma_free(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, unsigned long attrs)
{
- if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
- /* vaddr is a struct page cookie, not a kernel address */
- __dma_direct_free_pages(dev, size, vaddr);
- } else if (!dma_free_from_pool(vaddr, PAGE_ALIGN(size))) {
+ if (!dma_free_from_pool(vaddr, PAGE_ALIGN(size))) {
phys_addr_t phys = dma_to_phys(dev, dma_handle);
struct page *page = pfn_to_page(__phys_to_pfn(phys));
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 13f0cb080a4d..62fa5a82a065 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -696,29 +696,12 @@ bool is_swiotlb_active(void)
static int __init swiotlb_create_debugfs(void)
{
- struct dentry *d_swiotlb_usage;
- struct dentry *ent;
-
- d_swiotlb_usage = debugfs_create_dir("swiotlb", NULL);
-
- if (!d_swiotlb_usage)
- return -ENOMEM;
-
- ent = debugfs_create_ulong("io_tlb_nslabs", 0400,
- d_swiotlb_usage, &io_tlb_nslabs);
- if (!ent)
- goto fail;
-
- ent = debugfs_create_ulong("io_tlb_used", 0400,
- d_swiotlb_usage, &io_tlb_used);
- if (!ent)
- goto fail;
+ struct dentry *root;
+ root = debugfs_create_dir("swiotlb", NULL);
+ debugfs_create_ulong("io_tlb_nslabs", 0400, root, &io_tlb_nslabs);
+ debugfs_create_ulong("io_tlb_used", 0400, root, &io_tlb_used);
return 0;
-
-fail:
- debugfs_remove_recursive(d_swiotlb_usage);
- return -ENOMEM;
}
late_initcall(swiotlb_create_debugfs);
diff --git a/kernel/fail_function.c b/kernel/fail_function.c
index feb80712b913..63b349168da7 100644
--- a/kernel/fail_function.c
+++ b/kernel/fail_function.c
@@ -152,20 +152,13 @@ static int fei_retval_get(void *data, u64 *val)
DEFINE_DEBUGFS_ATTRIBUTE(fei_retval_ops, fei_retval_get, fei_retval_set,
"%llx\n");
-static int fei_debugfs_add_attr(struct fei_attr *attr)
+static void fei_debugfs_add_attr(struct fei_attr *attr)
{
struct dentry *dir;
dir = debugfs_create_dir(attr->kp.symbol_name, fei_debugfs_dir);
- if (!dir)
- return -ENOMEM;
-
- if (!debugfs_create_file("retval", 0600, dir, attr, &fei_retval_ops)) {
- debugfs_remove_recursive(dir);
- return -ENOMEM;
- }
- return 0;
+ debugfs_create_file("retval", 0600, dir, attr, &fei_retval_ops);
}
static void fei_debugfs_remove_attr(struct fei_attr *attr)
@@ -306,7 +299,7 @@ static ssize_t fei_write(struct file *file, const char __user *buffer,
ret = register_kprobe(&attr->kp);
if (!ret)
- ret = fei_debugfs_add_attr(attr);
+ fei_debugfs_add_attr(attr);
if (ret < 0)
fei_attr_remove(attr);
else {
@@ -337,19 +330,13 @@ static int __init fei_debugfs_init(void)
return PTR_ERR(dir);
/* injectable attribute is just a symlink of error_inject/list */
- if (!debugfs_create_symlink("injectable", dir,
- "../error_injection/list"))
- goto error;
+ debugfs_create_symlink("injectable", dir, "../error_injection/list");
- if (!debugfs_create_file("inject", 0600, dir, NULL, &fei_ops))
- goto error;
+ debugfs_create_file("inject", 0600, dir, NULL, &fei_ops);
fei_debugfs_dir = dir;
return 0;
-error:
- debugfs_remove_recursive(dir);
- return -ENOMEM;
}
late_initcall(fei_debugfs_init);
diff --git a/kernel/gcov/fs.c b/kernel/gcov/fs.c
index 6e40ff6be083..e5eb5ea7ea59 100644
--- a/kernel/gcov/fs.c
+++ b/kernel/gcov/fs.c
@@ -64,7 +64,6 @@ struct gcov_node {
static const char objtree[] = OBJTREE;
static const char srctree[] = SRCTREE;
static struct gcov_node root_node;
-static struct dentry *reset_dentry;
static LIST_HEAD(all_head);
static DEFINE_MUTEX(node_lock);
@@ -387,8 +386,6 @@ static void add_links(struct gcov_node *node, struct dentry *parent)
goto out_err;
node->links[i] = debugfs_create_symlink(deskew(basename),
parent, target);
- if (!node->links[i])
- goto out_err;
kfree(target);
}
@@ -450,11 +447,6 @@ static struct gcov_node *new_node(struct gcov_node *parent,
parent->dentry, node, &gcov_data_fops);
} else
node->dentry = debugfs_create_dir(node->name, parent->dentry);
- if (!node->dentry) {
- pr_warn("could not create file\n");
- kfree(node);
- return NULL;
- }
if (info)
add_links(node, parent->dentry);
list_add(&node->list, &parent->children);
@@ -761,32 +753,20 @@ void gcov_event(enum gcov_action action, struct gcov_info *info)
/* Create debugfs entries. */
static __init int gcov_fs_init(void)
{
- int rc = -EIO;
-
init_node(&root_node, NULL, NULL, NULL);
/*
* /sys/kernel/debug/gcov will be parent for the reset control file
* and all profiling files.
*/
root_node.dentry = debugfs_create_dir("gcov", NULL);
- if (!root_node.dentry)
- goto err_remove;
/*
* Create reset file which resets all profiling counts when written
* to.
*/
- reset_dentry = debugfs_create_file("reset", 0600, root_node.dentry,
- NULL, &gcov_reset_fops);
- if (!reset_dentry)
- goto err_remove;
+ debugfs_create_file("reset", 0600, root_node.dentry, NULL,
+ &gcov_reset_fops);
/* Replay previous events to get our fs hierarchy up-to-date. */
gcov_enable_events();
return 0;
-
-err_remove:
- pr_err("init failed\n");
- debugfs_remove(root_node.dentry);
-
- return rc;
}
device_initcall(gcov_fs_init);
diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh
index 9a34e1d9bd7f..9ff449888d9c 100755
--- a/kernel/gen_kheaders.sh
+++ b/kernel/gen_kheaders.sh
@@ -4,24 +4,12 @@
# This script generates an archive consisting of kernel headers
# for CONFIG_IKHEADERS.
set -e
-spath="$(dirname "$(readlink -f "$0")")"
-kroot="$spath/.."
+sfile="$(readlink -f "$0")"
outdir="$(pwd)"
tarfile=$1
cpio_dir=$outdir/$tarfile.tmp
-# Script filename relative to the kernel source root
-# We add it to the archive because it is small and any changes
-# to this script will also cause a rebuild of the archive.
-sfile="$(realpath --relative-to $kroot "$(readlink -f "$0")")"
-
-src_file_list="
-include/
-arch/$SRCARCH/include/
-$sfile
-"
-
-obj_file_list="
+dir_list="
include/
arch/$SRCARCH/include/
"
@@ -33,33 +21,29 @@ arch/$SRCARCH/include/
# Uncomment it for debugging.
# if [ ! -f /tmp/iter ]; then iter=1; echo 1 > /tmp/iter;
# else iter=$(($(cat /tmp/iter) + 1)); echo $iter > /tmp/iter; fi
-# find $src_file_list -type f | xargs ls -lR > /tmp/src-ls-$iter
-# find $obj_file_list -type f | xargs ls -lR > /tmp/obj-ls-$iter
+# find $src_file_list -name "*.h" | xargs ls -l > /tmp/src-ls-$iter
+# find $obj_file_list -name "*.h" | xargs ls -l > /tmp/obj-ls-$iter
# include/generated/compile.h is ignored because it is touched even when none
# of the source files changed. This causes pointless regeneration, so let us
# ignore them for md5 calculation.
-pushd $kroot > /dev/null
-src_files_md5="$(find $src_file_list -type f |
+pushd $srctree > /dev/null
+src_files_md5="$(find $dir_list -name "*.h" |
grep -v "include/generated/compile.h" |
grep -v "include/generated/autoconf.h" |
- grep -v "include/config/auto.conf" |
- grep -v "include/config/auto.conf.cmd" |
- grep -v "include/config/tristate.conf" |
- xargs ls -lR | md5sum | cut -d ' ' -f1)"
+ xargs ls -l | md5sum | cut -d ' ' -f1)"
popd > /dev/null
-obj_files_md5="$(find $obj_file_list -type f |
+obj_files_md5="$(find $dir_list -name "*.h" |
grep -v "include/generated/compile.h" |
grep -v "include/generated/autoconf.h" |
- grep -v "include/config/auto.conf" |
- grep -v "include/config/auto.conf.cmd" |
- grep -v "include/config/tristate.conf" |
- xargs ls -lR | md5sum | cut -d ' ' -f1)"
-
+ xargs ls -l | md5sum | cut -d ' ' -f1)"
+# Any changes to this script will also cause a rebuild of the archive.
+this_file_md5="$(ls -l $sfile | md5sum | cut -d ' ' -f1)"
if [ -f $tarfile ]; then tarfile_md5="$(md5sum $tarfile | cut -d ' ' -f1)"; fi
if [ -f kernel/kheaders.md5 ] &&
[ "$(cat kernel/kheaders.md5|head -1)" == "$src_files_md5" ] &&
[ "$(cat kernel/kheaders.md5|head -2|tail -1)" == "$obj_files_md5" ] &&
+ [ "$(cat kernel/kheaders.md5|head -3|tail -1)" == "$this_file_md5" ] &&
[ "$(cat kernel/kheaders.md5|tail -1)" == "$tarfile_md5" ]; then
exit
fi
@@ -71,16 +55,16 @@ fi
rm -rf $cpio_dir
mkdir $cpio_dir
-pushd $kroot > /dev/null
-for f in $src_file_list;
- do find "$f" ! -name "*.cmd" ! -name ".*";
+pushd $srctree > /dev/null
+for f in $dir_list;
+ do find "$f" -name "*.h";
done | cpio --quiet -pd $cpio_dir
popd > /dev/null
# The second CPIO can complain if files already exist which can
# happen with out of tree builds. Just silence CPIO for now.
-for f in $obj_file_list;
- do find "$f" ! -name "*.cmd" ! -name ".*";
+for f in $dir_list;
+ do find "$f" -name "*.h";
done | cpio --quiet -pd $cpio_dir >/dev/null 2>&1
# Remove comments except SDPX lines
@@ -91,6 +75,7 @@ tar -Jcf $tarfile -C $cpio_dir/ . > /dev/null
echo "$src_files_md5" > kernel/kheaders.md5
echo "$obj_files_md5" >> kernel/kheaders.md5
+echo "$this_file_md5" >> kernel/kheaders.md5
echo "$(md5sum $tarfile | cut -d ' ' -f1)" >> kernel/kheaders.md5
rm -rf $cpio_dir
diff --git a/kernel/iomem.c b/kernel/iomem.c
index 93c264444510..62c92e43aa0d 100644
--- a/kernel/iomem.c
+++ b/kernel/iomem.c
@@ -121,7 +121,7 @@ EXPORT_SYMBOL(memremap);
void memunmap(void *addr)
{
- if (is_vmalloc_addr(addr))
+ if (is_ioremap_addr(addr))
iounmap((void __iomem *) addr);
}
EXPORT_SYMBOL(memunmap);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 445337c107e0..9f5433a52488 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -2570,33 +2570,20 @@ static const struct file_operations fops_kp = {
static int __init debugfs_kprobe_init(void)
{
- struct dentry *dir, *file;
+ struct dentry *dir;
unsigned int value = 1;
dir = debugfs_create_dir("kprobes", NULL);
- if (!dir)
- return -ENOMEM;
- file = debugfs_create_file("list", 0400, dir, NULL,
- &debugfs_kprobes_operations);
- if (!file)
- goto error;
+ debugfs_create_file("list", 0400, dir, NULL,
+ &debugfs_kprobes_operations);
- file = debugfs_create_file("enabled", 0600, dir,
- &value, &fops_kp);
- if (!file)
- goto error;
+ debugfs_create_file("enabled", 0600, dir, &value, &fops_kp);
- file = debugfs_create_file("blacklist", 0400, dir, NULL,
- &debugfs_kprobe_blacklist_ops);
- if (!file)
- goto error;
+ debugfs_create_file("blacklist", 0400, dir, NULL,
+ &debugfs_kprobe_blacklist_ops);
return 0;
-
-error:
- debugfs_remove(dir);
- return -ENOMEM;
}
late_initcall(debugfs_kprobe_init);
diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c
index abb2a4a2cbb2..cdf318d86dd6 100644
--- a/kernel/livepatch/transition.c
+++ b/kernel/livepatch/transition.c
@@ -247,7 +247,6 @@ static int klp_check_stack(struct task_struct *task, char *err_buf)
int ret, nr_entries;
ret = stack_trace_save_tsk_reliable(task, entries, ARRAY_SIZE(entries));
- WARN_ON_ONCE(ret == -ENOSYS);
if (ret < 0) {
snprintf(err_buf, STACK_ERR_BUF_SIZE,
"%s: %s:%d has an unreliable stack\n",
@@ -281,11 +280,11 @@ static int klp_check_stack(struct task_struct *task, char *err_buf)
*/
static bool klp_try_switch_task(struct task_struct *task)
{
+ static char err_buf[STACK_ERR_BUF_SIZE];
struct rq *rq;
struct rq_flags flags;
int ret;
bool success = false;
- char err_buf[STACK_ERR_BUF_SIZE];
err_buf[0] = '\0';
@@ -294,6 +293,13 @@ static bool klp_try_switch_task(struct task_struct *task)
return true;
/*
+ * For arches which don't have reliable stack traces, we have to rely
+ * on other methods (e.g., switching tasks at kernel exit).
+ */
+ if (!klp_have_reliable_stack())
+ return false;
+
+ /*
* Now try to check the stack for any to-be-patched or to-be-unpatched
* functions. If all goes well, switch the task to the target patch
* state.
@@ -328,7 +334,6 @@ done:
pr_debug("%s", err_buf);
return success;
-
}
/*
diff --git a/kernel/stacktrace.c b/kernel/stacktrace.c
index 36139de0a3c4..e6a02b274b73 100644
--- a/kernel/stacktrace.c
+++ b/kernel/stacktrace.c
@@ -228,7 +228,7 @@ unsigned int stack_trace_save_user(unsigned long *store, unsigned int size)
};
/* Trace user stack if not a kernel thread */
- if (!current->mm)
+ if (current->flags & PF_KTHREAD)
return 0;
arch_stack_walk_user(consume_entry, &c, task_pt_regs(current));
@@ -255,14 +255,6 @@ save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
WARN_ONCE(1, KERN_INFO "save_stack_trace_regs() not implemented yet.\n");
}
-__weak int
-save_stack_trace_tsk_reliable(struct task_struct *tsk,
- struct stack_trace *trace)
-{
- WARN_ONCE(1, KERN_INFO "save_stack_tsk_reliable() not implemented yet.\n");
- return -ENOSYS;
-}
-
/**
* stack_trace_save - Save a stack trace into a storage array
* @store: Pointer to storage array
diff --git a/kernel/time/vsyscall.c b/kernel/time/vsyscall.c
index a80893180826..8cf3596a4ce6 100644
--- a/kernel/time/vsyscall.c
+++ b/kernel/time/vsyscall.c
@@ -104,11 +104,7 @@ void update_vsyscall(struct timekeeper *tk)
vdso_ts->sec = tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift;
nsec = nsec + tk->wall_to_monotonic.tv_nsec;
- while (nsec >= NSEC_PER_SEC) {
- nsec = nsec - NSEC_PER_SEC;
- vdso_ts->sec++;
- }
- vdso_ts->nsec = nsec;
+ vdso_ts->sec += __iter_div_u64_rem(nsec, NSEC_PER_SEC, &vdso_ts->nsec);
if (__arch_use_vsyscall(vdata))
update_vdso_data(vdata, tk);
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index e1c6d79fb4cc..2d6e93ab0478 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -512,8 +512,6 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
dir = debugfs_lookup(buts->name, blk_debugfs_root);
if (!dir)
bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root);
- if (!dir)
- goto err;
bt->dev = dev;
atomic_set(&bt->dropped, 0);
@@ -522,12 +520,8 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
ret = -EIO;
bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt,
&blk_dropped_fops);
- if (!bt->dropped_file)
- goto err;
bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops);
- if (!bt->msg_file)
- goto err;
bt->rchan = relay_open("trace", dir, buts->buf_size,
buts->buf_nr, &blk_relay_callbacks, bt);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c3aabb576fe5..c90c687cf950 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -8618,10 +8618,6 @@ struct dentry *tracing_init_dentry(void)
*/
tr->dir = debugfs_create_automount("tracing", NULL,
trace_automount, NULL);
- if (!tr->dir) {
- pr_warn_once("Could not create debugfs directory 'tracing'\n");
- return ERR_PTR(-ENOMEM);
- }
return NULL;
}