| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <a47d850b0111735e026d438c3300c0e3b7f439f4.1750433500.git.lorenzo.stoakes@oracle.com>
Date: Fri, 20 Jun 2025 16:33:02 +0100
From: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: David Hildenbrand <david@...hat.com>, Zi Yan <ziy@...dia.com>,
Baolin Wang <baolin.wang@...ux.alibaba.com>,
"Liam R . Howlett" <Liam.Howlett@...cle.com>,
Nico Pache <npache@...hat.com>, Ryan Roberts <ryan.roberts@....com>,
Dev Jain <dev.jain@....com>, Barry Song <baohua@...nel.org>,
Vlastimil Babka <vbabka@...e.cz>, Jann Horn <jannh@...gle.com>,
linux-mm@...ck.org, linux-kernel@...r.kernel.org,
Lance Yang <ioworker0@...il.com>, SeongJae Park <sj@...nel.org>,
Suren Baghdasaryan <surenb@...gle.com>
Subject: [PATCH v2 2/5] mm/madvise: thread mm_struct through madvise_behavior
There's no need to thread a pointer to the mm_struct nor have different
functions signatures for each behaviour, instead store state in the struct
madvise_behavior object consistently and use it for all madvise() actions.
Reviewed-by: Vlastimil Babka <vbabka@...e.cz>
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@...cle.com>
---
mm/madvise.c | 110 ++++++++++++++++++++++++++-------------------------
1 file changed, 57 insertions(+), 53 deletions(-)
diff --git a/mm/madvise.c b/mm/madvise.c
index 93837b980cc2..f1109c2c63a4 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -58,6 +58,7 @@ enum madvise_lock_mode {
};
struct madvise_behavior {
+ struct mm_struct *mm;
int behavior;
struct mmu_gather *tlb;
enum madvise_lock_mode lock_mode;
@@ -65,8 +66,8 @@ struct madvise_behavior {
};
#ifdef CONFIG_ANON_VMA_NAME
-static int madvise_walk_vmas(struct mm_struct *mm, unsigned long start,
- unsigned long end, struct madvise_behavior *madv_behavior);
+static int madvise_walk_vmas(unsigned long start, unsigned long end,
+ struct madvise_behavior *madv_behavior);
struct anon_vma_name *anon_vma_name_alloc(const char *name)
{
@@ -125,6 +126,7 @@ int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
unsigned long end;
unsigned long len;
struct madvise_behavior madv_behavior = {
+ .mm = mm,
.behavior = __MADV_SET_ANON_VMA_NAME,
.lock_mode = MADVISE_MMAP_WRITE_LOCK,
.anon_name = anon_name,
@@ -145,7 +147,7 @@ int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
if (end == start)
return 0;
- return madvise_walk_vmas(mm, start, end, &madv_behavior);
+ return madvise_walk_vmas(start, end, &madv_behavior);
}
#else /* CONFIG_ANON_VMA_NAME */
static int replace_anon_vma_name(struct vm_area_struct *vma,
@@ -991,10 +993,11 @@ static long madvise_dontneed_free(struct vm_area_struct *vma,
return -EINVAL;
}
-static long madvise_populate(struct mm_struct *mm, unsigned long start,
- unsigned long end, int behavior)
+static long madvise_populate(unsigned long start, unsigned long end,
+ struct madvise_behavior *madv_behavior)
{
- const bool write = behavior == MADV_POPULATE_WRITE;
+ struct mm_struct *mm = madv_behavior->mm;
+ const bool write = madv_behavior->behavior == MADV_POPULATE_WRITE;
int locked = 1;
long pages;
@@ -1408,15 +1411,14 @@ static int madvise_vma_behavior(struct vm_area_struct *vma,
/*
* Error injection support for memory error handling.
*/
-static int madvise_inject_error(int behavior,
- unsigned long start, unsigned long end)
+static int madvise_inject_error(unsigned long start, unsigned long end,
+ struct madvise_behavior *madv_behavior)
{
unsigned long size;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
-
for (; start < end; start += size) {
unsigned long pfn;
struct page *page;
@@ -1434,7 +1436,7 @@ static int madvise_inject_error(int behavior,
*/
size = page_size(compound_head(page));
- if (behavior == MADV_SOFT_OFFLINE) {
+ if (madv_behavior->behavior == MADV_SOFT_OFFLINE) {
pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n",
pfn, start);
ret = soft_offline_page(pfn, MF_COUNT_INCREASED);
@@ -1453,9 +1455,9 @@ static int madvise_inject_error(int behavior,
return 0;
}
-static bool is_memory_failure(int behavior)
+static bool is_memory_failure(struct madvise_behavior *madv_behavior)
{
- switch (behavior) {
+ switch (madv_behavior->behavior) {
case MADV_HWPOISON:
case MADV_SOFT_OFFLINE:
return true;
@@ -1466,13 +1468,13 @@ static bool is_memory_failure(int behavior)
#else
-static int madvise_inject_error(int behavior,
- unsigned long start, unsigned long end)
+static int madvise_inject_error(unsigned long start, unsigned long end,
+ struct madvise_behavior *madv_behavior)
{
return 0;
}
-static bool is_memory_failure(int behavior)
+static bool is_memory_failure(struct madvise_behavior *madv_behavior)
{
return false;
}
@@ -1549,10 +1551,11 @@ static bool process_madvise_remote_valid(int behavior)
* If a VMA read lock could not be acquired, we return NULL and expect caller to
* fallback to mmap lock behaviour.
*/
-static struct vm_area_struct *try_vma_read_lock(struct mm_struct *mm,
+static struct vm_area_struct *try_vma_read_lock(
struct madvise_behavior *madv_behavior,
unsigned long start, unsigned long end)
{
+ struct mm_struct *mm = madv_behavior->mm;
struct vm_area_struct *vma;
vma = lock_vma_under_rcu(mm, start);
@@ -1585,9 +1588,10 @@ static struct vm_area_struct *try_vma_read_lock(struct mm_struct *mm,
* reading or writing.
*/
static
-int madvise_walk_vmas(struct mm_struct *mm, unsigned long start,
- unsigned long end, struct madvise_behavior *madv_behavior)
+int madvise_walk_vmas(unsigned long start, unsigned long end,
+ struct madvise_behavior *madv_behavior)
{
+ struct mm_struct *mm = madv_behavior->mm;
struct vm_area_struct *vma;
struct vm_area_struct *prev;
unsigned long tmp;
@@ -1599,7 +1603,7 @@ int madvise_walk_vmas(struct mm_struct *mm, unsigned long start,
* tentatively, avoiding walking VMAs.
*/
if (madv_behavior->lock_mode == MADVISE_VMA_READ_LOCK) {
- vma = try_vma_read_lock(mm, madv_behavior, start, end);
+ vma = try_vma_read_lock(madv_behavior, start, end);
if (vma) {
prev = vma;
error = madvise_vma_behavior(vma, &prev, start, end,
@@ -1662,12 +1666,10 @@ int madvise_walk_vmas(struct mm_struct *mm, unsigned long start,
*/
static enum madvise_lock_mode get_lock_mode(struct madvise_behavior *madv_behavior)
{
- int behavior = madv_behavior->behavior;
-
- if (is_memory_failure(behavior))
+ if (is_memory_failure(madv_behavior))
return MADVISE_NO_LOCK;
- switch (behavior) {
+ switch (madv_behavior->behavior) {
case MADV_REMOVE:
case MADV_WILLNEED:
case MADV_COLD:
@@ -1687,9 +1689,9 @@ static enum madvise_lock_mode get_lock_mode(struct madvise_behavior *madv_behavi
}
}
-static int madvise_lock(struct mm_struct *mm,
- struct madvise_behavior *madv_behavior)
+static int madvise_lock(struct madvise_behavior *madv_behavior)
{
+ struct mm_struct *mm = madv_behavior->mm;
enum madvise_lock_mode lock_mode = get_lock_mode(madv_behavior);
switch (lock_mode) {
@@ -1711,9 +1713,10 @@ static int madvise_lock(struct mm_struct *mm,
return 0;
}
-static void madvise_unlock(struct mm_struct *mm,
- struct madvise_behavior *madv_behavior)
+static void madvise_unlock(struct madvise_behavior *madv_behavior)
{
+ struct mm_struct *mm = madv_behavior->mm;
+
switch (madv_behavior->lock_mode) {
case MADVISE_NO_LOCK:
return;
@@ -1743,11 +1746,10 @@ static bool madvise_batch_tlb_flush(int behavior)
}
}
-static void madvise_init_tlb(struct madvise_behavior *madv_behavior,
- struct mm_struct *mm)
+static void madvise_init_tlb(struct madvise_behavior *madv_behavior)
{
if (madvise_batch_tlb_flush(madv_behavior->behavior))
- tlb_gather_mmu(madv_behavior->tlb, mm);
+ tlb_gather_mmu(madv_behavior->tlb, madv_behavior->mm);
}
static void madvise_finish_tlb(struct madvise_behavior *madv_behavior)
@@ -1802,9 +1804,9 @@ static bool madvise_should_skip(unsigned long start, size_t len_in,
return false;
}
-static bool is_madvise_populate(int behavior)
+static bool is_madvise_populate(struct madvise_behavior *madv_behavior)
{
- switch (behavior) {
+ switch (madv_behavior->behavior) {
case MADV_POPULATE_READ:
case MADV_POPULATE_WRITE:
return true;
@@ -1828,25 +1830,26 @@ static inline unsigned long get_untagged_addr(struct mm_struct *mm,
untagged_addr_remote(mm, start);
}
-static int madvise_do_behavior(struct mm_struct *mm,
- unsigned long start, size_t len_in,
+static int madvise_do_behavior(unsigned long start, size_t len_in,
struct madvise_behavior *madv_behavior)
{
- int behavior = madv_behavior->behavior;
struct blk_plug plug;
unsigned long end;
int error;
- if (is_memory_failure(behavior))
- return madvise_inject_error(behavior, start, start + len_in);
- start = get_untagged_addr(mm, start);
+ if (is_memory_failure(madv_behavior)) {
+ end = start + len_in;
+ return madvise_inject_error(start, end, madv_behavior);
+ }
+
+ start = get_untagged_addr(madv_behavior->mm, start);
end = start + PAGE_ALIGN(len_in);
blk_start_plug(&plug);
- if (is_madvise_populate(behavior))
- error = madvise_populate(mm, start, end, behavior);
+ if (is_madvise_populate(madv_behavior))
+ error = madvise_populate(start, end, madv_behavior);
else
- error = madvise_walk_vmas(mm, start, end, madv_behavior);
+ error = madvise_walk_vmas(start, end, madv_behavior);
blk_finish_plug(&plug);
return error;
}
@@ -1928,19 +1931,20 @@ int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int beh
int error;
struct mmu_gather tlb;
struct madvise_behavior madv_behavior = {
+ .mm = mm,
.behavior = behavior,
.tlb = &tlb,
};
if (madvise_should_skip(start, len_in, behavior, &error))
return error;
- error = madvise_lock(mm, &madv_behavior);
+ error = madvise_lock(&madv_behavior);
if (error)
return error;
- madvise_init_tlb(&madv_behavior, mm);
- error = madvise_do_behavior(mm, start, len_in, &madv_behavior);
+ madvise_init_tlb(&madv_behavior);
+ error = madvise_do_behavior(start, len_in, &madv_behavior);
madvise_finish_tlb(&madv_behavior);
- madvise_unlock(mm, &madv_behavior);
+ madvise_unlock(&madv_behavior);
return error;
}
@@ -1958,16 +1962,17 @@ static ssize_t vector_madvise(struct mm_struct *mm, struct iov_iter *iter,
size_t total_len;
struct mmu_gather tlb;
struct madvise_behavior madv_behavior = {
+ .mm = mm,
.behavior = behavior,
.tlb = &tlb,
};
total_len = iov_iter_count(iter);
- ret = madvise_lock(mm, &madv_behavior);
+ ret = madvise_lock(&madv_behavior);
if (ret)
return ret;
- madvise_init_tlb(&madv_behavior, mm);
+ madvise_init_tlb(&madv_behavior);
while (iov_iter_count(iter)) {
unsigned long start = (unsigned long)iter_iov_addr(iter);
@@ -1977,8 +1982,7 @@ static ssize_t vector_madvise(struct mm_struct *mm, struct iov_iter *iter,
if (madvise_should_skip(start, len_in, behavior, &error))
ret = error;
else
- ret = madvise_do_behavior(mm, start, len_in,
- &madv_behavior);
+ ret = madvise_do_behavior(start, len_in, &madv_behavior);
/*
* An madvise operation is attempting to restart the syscall,
* but we cannot proceed as it would not be correct to repeat
@@ -1997,11 +2001,11 @@ static ssize_t vector_madvise(struct mm_struct *mm, struct iov_iter *iter,
/* Drop and reacquire lock to unwind race. */
madvise_finish_tlb(&madv_behavior);
- madvise_unlock(mm, &madv_behavior);
- ret = madvise_lock(mm, &madv_behavior);
+ madvise_unlock(&madv_behavior);
+ ret = madvise_lock(&madv_behavior);
if (ret)
goto out;
- madvise_init_tlb(&madv_behavior, mm);
+ madvise_init_tlb(&madv_behavior);
continue;
}
if (ret < 0)
@@ -2009,7 +2013,7 @@ static ssize_t vector_madvise(struct mm_struct *mm, struct iov_iter *iter,
iov_iter_advance(iter, iter_iov_len(iter));
}
madvise_finish_tlb(&madv_behavior);
- madvise_unlock(mm, &madv_behavior);
+ madvise_unlock(&madv_behavior);
out:
ret = (total_len - iov_iter_count(iter)) ? : ret;
--
2.49.0
Powered by blists - more mailing lists