From: Steven Rostedt <rostedt(a)goodmis.org>
When adding a new fprobe, it will update the function hash to the
functions the fprobe is attached to and register with function graph to
have it call the registered functions. The fprobe_graph_active variable
keeps track of the number of fprobes that are using function graph.
If two fprobes attach to the same function, it increments the
fprobe_graph_active for each of them. But when they are removed, the first
fprobe to be removed will see that the function it is attached to is also
used by another fprobe and it will not remove that function from
function_graph. The logic will skip decrementing the fprobe_graph_active
variable.
This causes the fprobe_graph_active variable to not go to zero when all
fprobes are removed, and in doing so it does not unregister from
function graph. As the fgraph ops hash will now be empty, and an empty
filter hash means all functions are enabled, this triggers function graph
to add a callback to the fprobe infrastructure for every function!
# echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events
# echo "f:myevent2 kernel_clone%return" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc0024000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# > /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
trace_initcall_start_cb (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
try_to_run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
x86_pmu_show_pmu_cap (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
cleanup_rapl_pmus (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_free_pcibus_map (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_types_exit (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_pci_exit.part.0 (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
kvm_shutdown (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
vmx_dump_msrs (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
[..]
# cat /sys/kernel/tracing/enabled_functions | wc -l
54702
If a fprobe is being removed and all its functions are also traced by
other fprobes, still decrement the fprobe_graph_active counter.
Cc: stable(a)vger.kernel.org
Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
Closes: https://lore.kernel.org/all/20250217114918.10397-A-hca@linux.ibm.com/
Reported-by: Heiko Carstens <hca(a)linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org>
---
Changes since v1: https://lore.kernel.org/20250218193126.619197190@goodmis.org
- Move the check into fprobe_graph_remove_ips() to keep it matching
with fprobe_graph_add_ips() (Masami Hiramatsu)
kernel/trace/fprobe.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 62e8f7d56602..33082c4e8154 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -407,7 +407,8 @@ static void fprobe_graph_remove_ips(unsigned long *addrs, int num)
if (!fprobe_graph_active)
unregister_ftrace_graph(&fprobe_graph_ops);
- ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0);
+ if (num)
+ ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0);
}
static int symbols_cmp(const void *a, const void *b)
@@ -677,8 +678,7 @@ int unregister_fprobe(struct fprobe *fp)
}
del_fprobe_hash(fp);
- if (count)
- fprobe_graph_remove_ips(addrs, count);
+ fprobe_graph_remove_ips(addrs, count);
kfree_rcu(hlist_array, rcu);
fp->hlist_array = NULL;
--
2.47.2
From: Steven Rostedt <rostedt(a)goodmis.org>
When the last fprobe is removed, it calls unregister_ftrace_graph() to
remove the graph_ops from function graph. The issue is when it does so, it
calls return before removing the function from its graph ops via
ftrace_set_filter_ips(). This leaves the last function lingering in the
fprobe's fgraph ops and if a probe is added it also enables that last
function (even though the callback will just drop it, it does add unneeded
overhead to make that call).
# echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# echo "f:myevent2 schedule_timeout" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
schedule_timeout (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# > /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
# echo "f:myevent3 kmem_cache_free" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kmem_cache_free (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
schedule_timeout (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
The above enabled a fprobe on kernel_clone, and then on schedule_timeout.
The content of the enabled_functions shows the functions that have a
callback attached to them. The fprobe attached to those functions
properly. Then the fprobes were cleared, and enabled_functions was empty
after that. But after adding a fprobe on kmem_cache_free, the
enabled_functions shows that the schedule_timeout was attached again. This
is because it was still left in the fprobe ops that is used to tell
function graph what functions it wants callbacks from.
Cc: stable(a)vger.kernel.org
Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org>
---
kernel/trace/fprobe.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 2560b312ad57..62e8f7d56602 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -403,11 +403,9 @@ static void fprobe_graph_remove_ips(unsigned long *addrs, int num)
lockdep_assert_held(&fprobe_mutex);
fprobe_graph_active--;
- if (!fprobe_graph_active) {
- /* Q: should we unregister it ? */
+ /* Q: should we unregister it ? */
+ if (!fprobe_graph_active)
unregister_ftrace_graph(&fprobe_graph_ops);
- return;
- }
ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0);
}
--
2.47.2
When update_mmu_cache_range() is called by update_mmu_cache(), the vmf
parameter is NULL, which will cause a NULL pointer dereference issue in
adjust_pte():
Unable to handle kernel NULL pointer dereference at virtual address 00000030 when read
Hardware name: Atmel AT91SAM9
PC is at update_mmu_cache_range+0x1e0/0x278
LR is at pte_offset_map_rw_nolock+0x18/0x2c
Call trace:
update_mmu_cache_range from remove_migration_pte+0x29c/0x2ec
remove_migration_pte from rmap_walk_file+0xcc/0x130
rmap_walk_file from remove_migration_ptes+0x90/0xa4
remove_migration_ptes from migrate_pages_batch+0x6d4/0x858
migrate_pages_batch from migrate_pages+0x188/0x488
migrate_pages from compact_zone+0x56c/0x954
compact_zone from compact_node+0x90/0xf0
compact_node from kcompactd+0x1d4/0x204
kcompactd from kthread+0x120/0x12c
kthread from ret_from_fork+0x14/0x38
Exception stack(0xc0d8bfb0 to 0xc0d8bff8)
To fix it, do not rely on whether 'ptl' is equal to decide whether to hold
the pte lock, but decide it by whether CONFIG_SPLIT_PTE_PTLOCKS is
enabled. In addition, if two vmas map to the same PTE page, there is no
need to hold the pte lock again, otherwise a deadlock will occur. Just add
the need_lock parameter to let adjust_pte() know this information.
Reported-by: Ezra Buehler <ezra.buehler(a)husqvarnagroup.com>
Closes: https://lore.kernel.org/lkml/CAM1KZSmZ2T_riHvay+7cKEFxoPgeVpHkVFTzVVEQ1BO0c…
Fixes: fc9c45b71f43 ("arm: adjust_pte() use pte_offset_map_rw_nolock()")
Cc: stable(a)vger.kernel.org
Signed-off-by: Qi Zheng <zhengqi.arch(a)bytedance.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
---
Changes in v3:
- move pmd_start_addr and pmd_end_addr to the top and initialize directly
(David Hildenbrand)
- collect an Acked-by
Changes in v2:
- change Ezra's email address (Ezra Buehler)
- some cleanups (David Hildenbrand)
arch/arm/mm/fault-armv.c | 37 +++++++++++++++++++++++++------------
1 file changed, 25 insertions(+), 12 deletions(-)
diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c
index 2bec87c3327d2..39fd5df733178 100644
--- a/arch/arm/mm/fault-armv.c
+++ b/arch/arm/mm/fault-armv.c
@@ -62,7 +62,7 @@ static int do_adjust_pte(struct vm_area_struct *vma, unsigned long address,
}
static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
- unsigned long pfn, struct vm_fault *vmf)
+ unsigned long pfn, bool need_lock)
{
spinlock_t *ptl;
pgd_t *pgd;
@@ -99,12 +99,11 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
if (!pte)
return 0;
- /*
- * If we are using split PTE locks, then we need to take the page
- * lock here. Otherwise we are using shared mm->page_table_lock
- * which is already locked, thus cannot take it.
- */
- if (ptl != vmf->ptl) {
+ if (need_lock) {
+ /*
+ * Use nested version here to indicate that we are already
+ * holding one similar spinlock.
+ */
spin_lock_nested(ptl, SINGLE_DEPTH_NESTING);
if (unlikely(!pmd_same(pmdval, pmdp_get_lockless(pmd)))) {
pte_unmap_unlock(pte, ptl);
@@ -114,7 +113,7 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
ret = do_adjust_pte(vma, address, pfn, pte);
- if (ptl != vmf->ptl)
+ if (need_lock)
spin_unlock(ptl);
pte_unmap(pte);
@@ -123,9 +122,10 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address,
static void
make_coherent(struct address_space *mapping, struct vm_area_struct *vma,
- unsigned long addr, pte_t *ptep, unsigned long pfn,
- struct vm_fault *vmf)
+ unsigned long addr, pte_t *ptep, unsigned long pfn)
{
+ const unsigned long pmd_start_addr = ALIGN_DOWN(addr, PMD_SIZE);
+ const unsigned long pmd_end_addr = pmd_start_addr + PMD_SIZE;
struct mm_struct *mm = vma->vm_mm;
struct vm_area_struct *mpnt;
unsigned long offset;
@@ -141,6 +141,14 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma,
*/
flush_dcache_mmap_lock(mapping);
vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
+ /*
+ * If we are using split PTE locks, then we need to take the pte
+ * lock. Otherwise we are using shared mm->page_table_lock which
+ * is already locked, thus cannot take it.
+ */
+ bool need_lock = IS_ENABLED(CONFIG_SPLIT_PTE_PTLOCKS);
+ unsigned long mpnt_addr;
+
/*
* If this VMA is not in our MM, we can ignore it.
* Note that we intentionally mask out the VMA
@@ -151,7 +159,12 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma,
if (!(mpnt->vm_flags & VM_MAYSHARE))
continue;
offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
- aliases += adjust_pte(mpnt, mpnt->vm_start + offset, pfn, vmf);
+ mpnt_addr = mpnt->vm_start + offset;
+
+ /* Avoid deadlocks by not grabbing the same PTE lock again. */
+ if (mpnt_addr >= pmd_start_addr && mpnt_addr < pmd_end_addr)
+ need_lock = false;
+ aliases += adjust_pte(mpnt, mpnt_addr, pfn, need_lock);
}
flush_dcache_mmap_unlock(mapping);
if (aliases)
@@ -194,7 +207,7 @@ void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma,
__flush_dcache_folio(mapping, folio);
if (mapping) {
if (cache_is_vivt())
- make_coherent(mapping, vma, addr, ptep, pfn, vmf);
+ make_coherent(mapping, vma, addr, ptep, pfn);
else if (vma->vm_flags & VM_EXEC)
__flush_icache_all();
}
--
2.20.1
The patch titled
Subject: mm/hugetlb: wait for hugetlb folios to be freed
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-hugetlb-wait-for-hugetlb-folios-to-be-freed.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Ge Yang <yangge1116(a)126.com>
Subject: mm/hugetlb: wait for hugetlb folios to be freed
Date: Wed, 19 Feb 2025 11:46:44 +0800
Since the introduction of commit c77c0a8ac4c52 ("mm/hugetlb: defer freeing
of huge pages if in non-task context"), which supports deferring the
freeing of hugetlb pages, the allocation of contiguous memory through
cma_alloc() may fail probabilistically.
In the CMA allocation process, if it is found that the CMA area is
occupied by in-use hugetlb folios, these in-use hugetlb folios need to be
migrated to another location. When there are no available hugetlb folios
in the free hugetlb pool during the migration of in-use hugetlb folios,
new folios are allocated from the buddy system. A temporary state is set
on the newly allocated folio. Upon completion of the hugetlb folio
migration, the temporary state is transferred from the new folios to the
old folios. Normally, when the old folios with the temporary state are
freed, it is directly released back to the buddy system. However, due to
the deferred freeing of hugetlb pages, the PageBuddy() check fails,
ultimately leading to the failure of cma_alloc().
Here is a simplified call trace illustrating the process:
cma_alloc()
->__alloc_contig_migrate_range() // Migrate in-use hugetlb folios
->unmap_and_move_huge_page()
->folio_putback_hugetlb() // Free old folios
->test_pages_isolated()
->__test_page_isolated_in_pageblock()
->PageBuddy(page) // Check if the page is in buddy
To resolve this issue, we have implemented a function named
wait_for_freed_hugetlb_folios(). This function ensures that the hugetlb
folios are properly released back to the buddy system after their
migration is completed. By invoking wait_for_freed_hugetlb_folios()
before calling PageBuddy(), we ensure that PageBuddy() will succeed.
Link: https://lkml.kernel.org/r/1739936804-18199-1-git-send-email-yangge1116@126.…
Fixes: c77c0a8ac4c52 ("mm/hugetlb: defer freeing of huge pages if in non-task context")
Signed-off-by: Ge Yang <yangge1116(a)126.com>
Reviewed-by: Muchun Song <muchun.song(a)linux.dev>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Cc: Barry Song <21cnbao(a)gmail.com>
Cc: Oscar Salvador <osalvador(a)suse.de>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/hugetlb.h | 5 +++++
mm/hugetlb.c | 8 ++++++++
mm/page_isolation.c | 10 ++++++++++
3 files changed, 23 insertions(+)
--- a/include/linux/hugetlb.h~mm-hugetlb-wait-for-hugetlb-folios-to-be-freed
+++ a/include/linux/hugetlb.h
@@ -682,6 +682,7 @@ struct huge_bootmem_page {
int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list);
int replace_free_hugepage_folios(unsigned long start_pfn, unsigned long end_pfn);
+void wait_for_freed_hugetlb_folios(void);
struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma,
unsigned long addr, bool cow_from_owner);
struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid,
@@ -1066,6 +1067,10 @@ static inline int replace_free_hugepage_
return 0;
}
+static inline void wait_for_freed_hugetlb_folios(void)
+{
+}
+
static inline struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma,
unsigned long addr,
bool cow_from_owner)
--- a/mm/hugetlb.c~mm-hugetlb-wait-for-hugetlb-folios-to-be-freed
+++ a/mm/hugetlb.c
@@ -2943,6 +2943,14 @@ int replace_free_hugepage_folios(unsigne
return ret;
}
+void wait_for_freed_hugetlb_folios(void)
+{
+ if (llist_empty(&hpage_freelist))
+ return;
+
+ flush_work(&free_hpage_work);
+}
+
typedef enum {
/*
* For either 0/1: we checked the per-vma resv map, and one resv
--- a/mm/page_isolation.c~mm-hugetlb-wait-for-hugetlb-folios-to-be-freed
+++ a/mm/page_isolation.c
@@ -608,6 +608,16 @@ int test_pages_isolated(unsigned long st
int ret;
/*
+ * Due to the deferred freeing of hugetlb folios, the hugepage folios may
+ * not immediately release to the buddy system. This can cause PageBuddy()
+ * to fail in __test_page_isolated_in_pageblock(). To ensure that the
+ * hugetlb folios are properly released back to the buddy system, we
+ * invoke the wait_for_freed_hugetlb_folios() function to wait for the
+ * release to complete.
+ */
+ wait_for_freed_hugetlb_folios();
+
+ /*
* Note: pageblock_nr_pages != MAX_PAGE_ORDER. Then, chunks of free
* pages are not aligned to pageblock_nr_pages.
* Then we just check migratetype first.
_
Patches currently in -mm which might be from yangge1116(a)126.com are
mm-hugetlb-wait-for-hugetlb-folios-to-be-freed.patch
During the "size_check" label in ea_get(), the code checks if the extended
attribute list (xattr) size matches ea_size. If not, it logs
"ea_get: invalid extended attribute" and calls print_hex_dump().
Here, EALIST_SIZE(ea_buf->xattr) returns 4110417968, which exceeds
INT_MAX (2,147,483,647). Then ea_size is clamped:
int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr));
Although clamp_t aims to bound ea_size between 0 and 4110417968, the upper
limit is treated as an int, causing an overflow above 2^31 - 1. This leads
"size" to wrap around and become negative (-184549328).
The "size" is then passed to print_hex_dump() (called "len" in
print_hex_dump()), it is passed as type size_t (an unsigned
type), this is then stored inside a variable called
"int remaining", which is then assigned to "int linelen" which
is then passed to hex_dump_to_buffer(). In print_hex_dump()
the for loop, iterates through 0 to len-1, where len is
18446744073525002176, calling hex_dump_to_buffer()
on each iteration:
for (i = 0; i < len; i += rowsize) {
linelen = min(remaining, rowsize);
remaining -= rowsize;
hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
linebuf, sizeof(linebuf), ascii);
...
}
The expected stopping condition (i < len) is effectively broken
since len is corrupted and very large. This eventually leads to
the "ptr+i" being passed to hex_dump_to_buffer() to get closer
to the end of the actual bounds of "ptr", eventually an out of
bounds access is done in hex_dump_to_buffer() in the following
for loop:
for (j = 0; j < len; j++) {
if (linebuflen < lx + 2)
goto overflow2;
ch = ptr[j];
...
}
To fix this we should validate "EALIST_SIZE(ea_buf->xattr)"
before it is utilised.
Reported-by: syzbot <syzbot+4e6e7e4279d046613bc5(a)syzkaller.appspotmail.com>
Tested-by: syzbot <syzbot+4e6e7e4279d046613bc5(a)syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=4e6e7e4279d046613bc5
Fixes: d9f9d96136cb ("jfs: xattr: check invalid xattr size more strictly")
Cc: stable(a)vger.kernel.org
Signed-off-by: Qasim Ijaz <qasdev00(a)gmail.com>
---
v2:
- Added Cc stable tag
fs/jfs/xattr.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index 24afbae87225..7575c51cce9b 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -559,11 +555,16 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
size_check:
if (EALIST_SIZE(ea_buf->xattr) != ea_size) {
- int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr));
-
- printk(KERN_ERR "ea_get: invalid extended attribute\n");
- print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1,
- ea_buf->xattr, size, 1);
+ if (unlikely(EALIST_SIZE(ea_buf->xattr) > INT_MAX)) {
+ printk(KERN_ERR "ea_get: extended attribute size too large: %u > INT_MAX\n",
+ EALIST_SIZE(ea_buf->xattr));
+ } else {
+ int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr));
+
+ printk(KERN_ERR "ea_get: invalid extended attribute\n");
+ print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1,
+ ea_buf->xattr, size, 1);
+ }
ea_release(inode, ea_buf);
rc = -EIO;
goto clean_up;
--
2.39.5
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x ccc45cb4e7271c74dbb27776ae8f73d84557f5c6
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023061111-tracing-shakiness-9054@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From ccc45cb4e7271c74dbb27776ae8f73d84557f5c6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20H=C3=B6ppner?= <hoeppner(a)linux.ibm.com>
Date: Fri, 9 Jun 2023 17:37:50 +0200
Subject: [PATCH] s390/dasd: Use correct lock while counting channel queue
length
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The lock around counting the channel queue length in the BIODASDINFO
ioctl was incorrectly changed to the dasd_block->queue_lock with commit
583d6535cb9d ("dasd: remove dead code"). This can lead to endless list
iterations and a subsequent crash.
The queue_lock is supposed to be used only for queue lists belonging to
dasd_block. For dasd_device related queue lists the ccwdev lock must be
used.
Fix the mentioned issues by correctly using the ccwdev lock instead of
the queue lock.
Fixes: 583d6535cb9d ("dasd: remove dead code")
Cc: stable(a)vger.kernel.org # v5.0+
Signed-off-by: Jan Höppner <hoeppner(a)linux.ibm.com>
Reviewed-by: Stefan Haberland <sth(a)linux.ibm.com>
Signed-off-by: Stefan Haberland <sth(a)linux.ibm.com>
Link: https://lore.kernel.org/r/20230609153750.1258763-2-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c
index 9327dcdd6e5e..8fca725b3dae 100644
--- a/drivers/s390/block/dasd_ioctl.c
+++ b/drivers/s390/block/dasd_ioctl.c
@@ -552,10 +552,10 @@ static int __dasd_ioctl_information(struct dasd_block *block,
memcpy(dasd_info->type, base->discipline->name, 4);
- spin_lock_irqsave(&block->queue_lock, flags);
+ spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
list_for_each(l, &base->ccw_queue)
dasd_info->chanq_len++;
- spin_unlock_irqrestore(&block->queue_lock, flags);
+ spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
return 0;
}
Hi,
I noticed there appears to be a regression in DLM (fs/dlm/) when
moving from Linux 5.4.229 to 5.4.288; I get a kernel panic when using
dlm_ls_lockx() (DLM user) with a timeout >0, and the panic occurs when
the timeout is reached (eg, attempting to take a lock on a resource
that is already locked); the host where the timeout occurs is the one
that panics:
...
[ 187.976007]
DLM: Assertion failed on line 1239 of file fs/dlm/lock.c
DLM: assertion: "!lkb->lkb_status"
DLM: time = 4294853632
[ 187.976009] lkb: nodeid 2 id 1 remid 2 exflags 40000 flags 800001
sts 1 rq 5 gr -1 wait_type 4 wait_nodeid 2 seq 0
[ 187.976009]
[ 187.976010] Kernel panic - not syncing: DLM: Record message above
and reboot.
[ 187.976099] CPU: 9 PID: 7409 Comm: dlm_scand Kdump: loaded Tainted:
P OE 5.4.288-esos.prod #1
[ 187.976195] Hardware name: Quantum H2012/H12SSW-NT, BIOS
T20201009143356 10/09/2020
[ 187.976282] Call Trace:
[ 187.976356] dump_stack+0x50/0x63
[ 187.976429] panic+0x10c/0x2e3
[ 187.976501] kill_lkb+0x51/0x52
[ 187.976570] kref_put+0x16/0x2f
[ 187.976638] __put_lkb+0x2f/0x95
[ 187.976707] dlm_scan_timeout+0x18b/0x19c
[ 187.976779] ? dlm_uevent+0x19/0x19
[ 187.976848] dlm_scand+0x94/0xd1
[ 187.976920] kthread+0xe4/0xe9
[ 187.976988] ? kthread_flush_worker+0x70/0x70
[ 187.977062] ret_from_fork+0x35/0x40
...
I examined the commits for fs/dlm/ between 5.4.229 and 5.4.288 and
this is the offender:
dlm: replace usage of found with dedicated list iterator variable
[ Upstream commit dc1acd5c94699389a9ed023e94dd860c846ea1f6 ]
Specifically, the change highlighted below in this hunk for
dlm_scan_timeout() in fs/dlm/lock.c:
@@ -1867,27 +1867,28 @@ void dlm_scan_timeout(struct dlm_ls *ls)
do_cancel = 0;
do_warn = 0;
mutex_lock(&ls->ls_timeout_mutex);
- list_for_each_entry(lkb, &ls->ls_timeout, lkb_time_list) {
+ list_for_each_entry(iter, &ls->ls_timeout, lkb_time_list) {
wait_us = ktime_to_us(ktime_sub(ktime_get(),
- lkb->lkb_timestamp));
+ iter->lkb_timestamp));
- if ((lkb->lkb_exflags & DLM_LKF_TIMEOUT) &&
- wait_us >= (lkb->lkb_timeout_cs * 10000))
+ if ((iter->lkb_exflags & DLM_LKF_TIMEOUT) &&
+ wait_us >= (iter->lkb_timeout_cs * 10000))
do_cancel = 1;
- if ((lkb->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
+ if ((iter->lkb_flags & DLM_IFL_WATCH_TIMEWARN) &&
wait_us >= dlm_config.ci_timewarn_cs * 10000)
do_warn = 1;
if (!do_cancel && !do_warn)
continue;
- hold_lkb(lkb);
+ hold_lkb(iter);
+ lkb = iter;
break;
}
mutex_unlock(&ls->ls_timeout_mutex);
- if (!do_cancel && !do_warn)
+ if (!lkb)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
break;
r = lkb->lkb_resource;
Reverting this single line change resolves the kernel panic:
$ diff -Naur fs/dlm/lock.c{.orig,}
--- fs/dlm/lock.c.orig 2024-12-19 12:05:05.000000000 -0500
+++ fs/dlm/lock.c 2025-02-16 21:21:42.544181390 -0500
@@ -1888,7 +1888,7 @@
}
mutex_unlock(&ls->ls_timeout_mutex);
- if (!lkb)
+ if (!do_cancel && !do_warn)
break;
r = lkb->lkb_resource;
It appears this same "dlm: replace usage of found with dedicated list
iterator variable" commit was pulled into other stable branches as
well, and I don't see any fix in the latest 5.4.x patch release
(5.4.290).
--Marc
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 8c8ecc98f5c65947b0070a24bac11e12e47cc65d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025021842-crusher-corrode-54d0@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 8c8ecc98f5c65947b0070a24bac11e12e47cc65d Mon Sep 17 00:00:00 2001
From: Sven Eckelmann <sven(a)narfation.org>
Date: Mon, 20 Jan 2025 00:06:11 +0100
Subject: [PATCH] batman-adv: Drop unmanaged ELP metric worker
The ELP worker needs to calculate new metric values for all neighbors
"reachable" over an interface. Some of the used metric sources require
locks which might need to sleep. This sleep is incompatible with the RCU
list iterator used for the recorded neighbors. The initial approach to work
around of this problem was to queue another work item per neighbor and then
run this in a new context.
Even when this solved the RCU vs might_sleep() conflict, it has a major
problems: Nothing was stopping the work item in case it is not needed
anymore - for example because one of the related interfaces was removed or
the batman-adv module was unloaded - resulting in potential invalid memory
accesses.
Directly canceling the metric worker also has various problems:
* cancel_work_sync for a to-be-deactivated interface is called with
rtnl_lock held. But the code in the ELP metric worker also tries to use
rtnl_lock() - which will never return in this case. This also means that
cancel_work_sync would never return because it is waiting for the worker
to finish.
* iterating over the neighbor list for the to-be-deactivated interface is
currently done using the RCU specific methods. Which means that it is
possible to miss items when iterating over it without the associated
spinlock - a behaviour which is acceptable for a periodic metric check
but not for a cleanup routine (which must "stop" all still running
workers)
The better approch is to get rid of the per interface neighbor metric
worker and handle everything in the interface worker. The original problems
are solved by:
* creating a list of neighbors which require new metric information inside
the RCU protected context, gathering the metric according to the new list
outside the RCU protected context
* only use rcu_trylock inside metric gathering code to avoid a deadlock
when the cancel_delayed_work_sync is called in the interface removal code
(which is called with the rtnl_lock held)
Cc: stable(a)vger.kernel.org
Fixes: c833484e5f38 ("batman-adv: ELP - compute the metric based on the estimated throughput")
Signed-off-by: Sven Eckelmann <sven(a)narfation.org>
Signed-off-by: Simon Wunderlich <sw(a)simonwunderlich.de>
diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c
index ac11f1f08db0..d35479c465e2 100644
--- a/net/batman-adv/bat_v.c
+++ b/net/batman-adv/bat_v.c
@@ -113,8 +113,6 @@ static void
batadv_v_hardif_neigh_init(struct batadv_hardif_neigh_node *hardif_neigh)
{
ewma_throughput_init(&hardif_neigh->bat_v.throughput);
- INIT_WORK(&hardif_neigh->bat_v.metric_work,
- batadv_v_elp_throughput_metric_update);
}
/**
diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index 65e52de52bcd..b065578b4436 100644
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -18,6 +18,7 @@
#include <linux/if_ether.h>
#include <linux/jiffies.h>
#include <linux/kref.h>
+#include <linux/list.h>
#include <linux/minmax.h>
#include <linux/netdevice.h>
#include <linux/nl80211.h>
@@ -26,6 +27,7 @@
#include <linux/rcupdate.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
+#include <linux/slab.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>
@@ -41,6 +43,18 @@
#include "routing.h"
#include "send.h"
+/**
+ * struct batadv_v_metric_queue_entry - list of hardif neighbors which require
+ * and metric update
+ */
+struct batadv_v_metric_queue_entry {
+ /** @hardif_neigh: hardif neighbor scheduled for metric update */
+ struct batadv_hardif_neigh_node *hardif_neigh;
+
+ /** @list: list node for metric_queue */
+ struct list_head list;
+};
+
/**
* batadv_v_elp_start_timer() - restart timer for ELP periodic work
* @hard_iface: the interface for which the timer has to be reset
@@ -137,10 +151,17 @@ static bool batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh,
goto default_throughput;
}
+ /* only use rtnl_trylock because the elp worker will be cancelled while
+ * the rntl_lock is held. the cancel_delayed_work_sync() would otherwise
+ * wait forever when the elp work_item was started and it is then also
+ * trying to rtnl_lock
+ */
+ if (!rtnl_trylock())
+ return false;
+
/* if not a wifi interface, check if this device provides data via
* ethtool (e.g. an Ethernet adapter)
*/
- rtnl_lock();
ret = __ethtool_get_link_ksettings(hard_iface->net_dev, &link_settings);
rtnl_unlock();
if (ret == 0) {
@@ -175,31 +196,19 @@ static bool batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh,
/**
* batadv_v_elp_throughput_metric_update() - worker updating the throughput
* metric of a single hop neighbour
- * @work: the work queue item
+ * @neigh: the neighbour to probe
*/
-void batadv_v_elp_throughput_metric_update(struct work_struct *work)
+static void
+batadv_v_elp_throughput_metric_update(struct batadv_hardif_neigh_node *neigh)
{
- struct batadv_hardif_neigh_node_bat_v *neigh_bat_v;
- struct batadv_hardif_neigh_node *neigh;
u32 throughput;
bool valid;
- neigh_bat_v = container_of(work, struct batadv_hardif_neigh_node_bat_v,
- metric_work);
- neigh = container_of(neigh_bat_v, struct batadv_hardif_neigh_node,
- bat_v);
-
valid = batadv_v_elp_get_throughput(neigh, &throughput);
if (!valid)
- goto put_neigh;
+ return;
ewma_throughput_add(&neigh->bat_v.throughput, throughput);
-
-put_neigh:
- /* decrement refcounter to balance increment performed before scheduling
- * this task
- */
- batadv_hardif_neigh_put(neigh);
}
/**
@@ -273,14 +282,16 @@ batadv_v_elp_wifi_neigh_probe(struct batadv_hardif_neigh_node *neigh)
*/
static void batadv_v_elp_periodic_work(struct work_struct *work)
{
+ struct batadv_v_metric_queue_entry *metric_entry;
+ struct batadv_v_metric_queue_entry *metric_safe;
struct batadv_hardif_neigh_node *hardif_neigh;
struct batadv_hard_iface *hard_iface;
struct batadv_hard_iface_bat_v *bat_v;
struct batadv_elp_packet *elp_packet;
+ struct list_head metric_queue;
struct batadv_priv *bat_priv;
struct sk_buff *skb;
u32 elp_interval;
- bool ret;
bat_v = container_of(work, struct batadv_hard_iface_bat_v, elp_wq.work);
hard_iface = container_of(bat_v, struct batadv_hard_iface, bat_v);
@@ -316,6 +327,8 @@ static void batadv_v_elp_periodic_work(struct work_struct *work)
atomic_inc(&hard_iface->bat_v.elp_seqno);
+ INIT_LIST_HEAD(&metric_queue);
+
/* The throughput metric is updated on each sent packet. This way, if a
* node is dead and no longer sends packets, batman-adv is still able to
* react timely to its death.
@@ -340,16 +353,28 @@ static void batadv_v_elp_periodic_work(struct work_struct *work)
/* Reading the estimated throughput from cfg80211 is a task that
* may sleep and that is not allowed in an rcu protected
- * context. Therefore schedule a task for that.
+ * context. Therefore add it to metric_queue and process it
+ * outside rcu protected context.
*/
- ret = queue_work(batadv_event_workqueue,
- &hardif_neigh->bat_v.metric_work);
-
- if (!ret)
+ metric_entry = kzalloc(sizeof(*metric_entry), GFP_ATOMIC);
+ if (!metric_entry) {
batadv_hardif_neigh_put(hardif_neigh);
+ continue;
+ }
+
+ metric_entry->hardif_neigh = hardif_neigh;
+ list_add(&metric_entry->list, &metric_queue);
}
rcu_read_unlock();
+ list_for_each_entry_safe(metric_entry, metric_safe, &metric_queue, list) {
+ batadv_v_elp_throughput_metric_update(metric_entry->hardif_neigh);
+
+ batadv_hardif_neigh_put(metric_entry->hardif_neigh);
+ list_del(&metric_entry->list);
+ kfree(metric_entry);
+ }
+
restart_timer:
batadv_v_elp_start_timer(hard_iface);
out:
diff --git a/net/batman-adv/bat_v_elp.h b/net/batman-adv/bat_v_elp.h
index 9e2740195fa2..c9cb0a307100 100644
--- a/net/batman-adv/bat_v_elp.h
+++ b/net/batman-adv/bat_v_elp.h
@@ -10,7 +10,6 @@
#include "main.h"
#include <linux/skbuff.h>
-#include <linux/workqueue.h>
int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface);
void batadv_v_elp_iface_disable(struct batadv_hard_iface *hard_iface);
@@ -19,6 +18,5 @@ void batadv_v_elp_iface_activate(struct batadv_hard_iface *primary_iface,
void batadv_v_elp_primary_iface_set(struct batadv_hard_iface *primary_iface);
int batadv_v_elp_packet_recv(struct sk_buff *skb,
struct batadv_hard_iface *if_incoming);
-void batadv_v_elp_throughput_metric_update(struct work_struct *work);
#endif /* _NET_BATMAN_ADV_BAT_V_ELP_H_ */
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 04f6398b3a40..85a50096f5b2 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -596,9 +596,6 @@ struct batadv_hardif_neigh_node_bat_v {
* neighbor
*/
unsigned long last_unicast_tx;
-
- /** @metric_work: work queue callback item for metric update */
- struct work_struct metric_work;
};
/**
commit c910f2b65518 ("arm64/mm: Update tlb invalidation routines for
FEAT_LPA2") changed the "invalidation level unknown" hint from 0 to
TLBI_TTL_UNKNOWN (INT_MAX). But the fallback "unknown level" path in
flush_hugetlb_tlb_range() was not updated. So as it stands, when trying
to invalidate CONT_PMD_SIZE or CONT_PTE_SIZE hugetlb mappings, we will
spuriously try to invalidate at level 0 on LPA2-enabled systems.
Fix this so that the fallback passes TLBI_TTL_UNKNOWN, and while we are
at it, explicitly use the correct stride and level for CONT_PMD_SIZE and
CONT_PTE_SIZE, which should provide a minor optimization.
Cc: stable(a)vger.kernel.org
Fixes: c910f2b65518 ("arm64/mm: Update tlb invalidation routines for FEAT_LPA2")
Signed-off-by: Ryan Roberts <ryan.roberts(a)arm.com>
---
arch/arm64/include/asm/hugetlb.h | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index 03db9cb21ace..07fbf5bf85a7 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -76,12 +76,22 @@ static inline void flush_hugetlb_tlb_range(struct vm_area_struct *vma,
{
unsigned long stride = huge_page_size(hstate_vma(vma));
- if (stride == PMD_SIZE)
- __flush_tlb_range(vma, start, end, stride, false, 2);
- else if (stride == PUD_SIZE)
- __flush_tlb_range(vma, start, end, stride, false, 1);
- else
- __flush_tlb_range(vma, start, end, PAGE_SIZE, false, 0);
+ switch (stride) {
+#ifndef __PAGETABLE_PMD_FOLDED
+ case PUD_SIZE:
+ __flush_tlb_range(vma, start, end, PUD_SIZE, false, 1);
+ break;
+#endif
+ case CONT_PMD_SIZE:
+ case PMD_SIZE:
+ __flush_tlb_range(vma, start, end, PMD_SIZE, false, 2);
+ break;
+ case CONT_PTE_SIZE:
+ __flush_tlb_range(vma, start, end, PAGE_SIZE, false, 3);
+ break;
+ default:
+ __flush_tlb_range(vma, start, end, PAGE_SIZE, false, TLBI_TTL_UNKNOWN);
+ }
}
#endif /* __ASM_HUGETLB_H */
--
2.43.0
From: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
When performing continuous unbind/bind operations on the USB drivers
available on the Renesas RZ/G2L SoC, a kernel crash with the message
"Unable to handle kernel NULL pointer dereference at virtual address"
may occur. This issue points to the usbhsc_notify_hotplug() function.
Flush the delayed work to avoid its execution when driver resources are
unavailable.
Fixes: bc57381e6347 ("usb: renesas_usbhs: use delayed_work instead of work_struct")
Cc: stable(a)vger.kernel.org
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
---
drivers/usb/renesas_usbhs/common.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/usb/renesas_usbhs/common.c b/drivers/usb/renesas_usbhs/common.c
index 6c7857b66a21..4b35ef216125 100644
--- a/drivers/usb/renesas_usbhs/common.c
+++ b/drivers/usb/renesas_usbhs/common.c
@@ -781,6 +781,8 @@ static void usbhs_remove(struct platform_device *pdev)
dev_dbg(&pdev->dev, "usb remove\n");
+ flush_delayed_work(&priv->notify_hotplug_work);
+
/* power off */
if (!usbhs_get_dparam(priv, runtime_pwctrl))
usbhsc_power_ctrl(priv, 0);
--
2.43.0
From: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
The gpriv->transceiver is retrieved in probe() through usb_get_phy() but
never released. Use devm_usb_get_phy() to handle this scenario.
This issue was identified through code investigation. No issue was found
without this change.
Fixes: b5a2875605ca ("usb: renesas_usbhs: Allow an OTG PHY driver to provide VBUS")
Cc: stable(a)vger.kernel.org
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
---
drivers/usb/renesas_usbhs/mod_gadget.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/renesas_usbhs/mod_gadget.c b/drivers/usb/renesas_usbhs/mod_gadget.c
index 105132ae87ac..e8e5723f5412 100644
--- a/drivers/usb/renesas_usbhs/mod_gadget.c
+++ b/drivers/usb/renesas_usbhs/mod_gadget.c
@@ -1094,7 +1094,7 @@ int usbhs_mod_gadget_probe(struct usbhs_priv *priv)
goto usbhs_mod_gadget_probe_err_gpriv;
}
- gpriv->transceiver = usb_get_phy(USB_PHY_TYPE_UNDEFINED);
+ gpriv->transceiver = devm_usb_get_phy(dev, USB_PHY_TYPE_UNDEFINED);
dev_info(dev, "%stransceiver found\n",
!IS_ERR(gpriv->transceiver) ? "" : "no ");
--
2.43.0
From: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
phy-rcar-gen3-usb2 driver exports 4 PHYs. The timing registers are common
to all PHYs. There is no need to set them every time a PHY is initialized.
Set timing register only when the 1st PHY is initialized.
Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
Cc: stable(a)vger.kernel.org
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
---
drivers/phy/renesas/phy-rcar-gen3-usb2.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
index 087937407b0b..8e57fa8c1cff 100644
--- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
@@ -467,8 +467,11 @@ static int rcar_gen3_phy_usb2_init(struct phy *p)
val = readl(usb2_base + USB2_INT_ENABLE);
val |= USB2_INT_ENABLE_UCOM_INTEN | rphy->int_enable_bits;
writel(val, usb2_base + USB2_INT_ENABLE);
- writel(USB2_SPD_RSM_TIMSET_INIT, usb2_base + USB2_SPD_RSM_TIMSET);
- writel(USB2_OC_TIMSET_INIT, usb2_base + USB2_OC_TIMSET);
+
+ if (!rcar_gen3_is_any_rphy_initialized(channel)) {
+ writel(USB2_SPD_RSM_TIMSET_INIT, usb2_base + USB2_SPD_RSM_TIMSET);
+ writel(USB2_OC_TIMSET_INIT, usb2_base + USB2_OC_TIMSET);
+ }
/* Initialize otg part (only if we initialize a PHY with IRQs). */
if (rphy->int_enable_bits)
--
2.43.0
From: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
The phy-rcar-gen3-usb2 driver exposes four individual PHYs that are
requested and configured by PHY users. The struct phy_ops APIs access the
same set of registers to configure all PHYs. Additionally, PHY settings can
be modified through sysfs or an IRQ handler. While some struct phy_ops APIs
are protected by a driver-wide mutex, others rely on individual
PHY-specific mutexes.
This approach can lead to various issues, including:
1/ the IRQ handler may interrupt PHY settings in progress, racing with
hardware configuration protected by a mutex lock
2/ due to msleep(20) in rcar_gen3_init_otg(), while a configuration thread
suspends to wait for the delay, another thread may try to configure
another PHY (with phy_init() + phy_power_on()); re-running the
phy_init() goes to the exact same configuration code, re-running the
same hardware configuration on the same set of registers (and bits)
which might impact the result of the msleep for the 1st configuring
thread
3/ sysfs can configure the hardware (though role_store()) and it can
still race with the phy_init()/phy_power_on() APIs calling into the
drivers struct phy_ops
To address these issues, add a spinlock to protect hardware register access
and driver private data structures (e.g., calls to
rcar_gen3_is_any_rphy_initialized()). Checking driver-specific data remains
necessary as all PHY instances share common settings. With this change,
the existing mutex protection is removed and the cleanup.h helpers are
used.
While at it, to keep the code simpler, do not skip
regulator_enable()/regulator_disable() APIs in
rcar_gen3_phy_usb2_power_on()/rcar_gen3_phy_usb2_power_off() as the
regulators enable/disable operations are reference counted anyway.
Fixes: f3b5a8d9b50d ("phy: rcar-gen3-usb2: Add R-Car Gen3 USB2 PHY driver")
Cc: stable(a)vger.kernel.org
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj(a)bp.renesas.com>
---
drivers/phy/renesas/phy-rcar-gen3-usb2.c | 49 +++++++++++++-----------
1 file changed, 26 insertions(+), 23 deletions(-)
diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
index 826c9c4dd4c0..5c0ceba09b67 100644
--- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
@@ -9,6 +9,7 @@
* Copyright (C) 2014 Cogent Embedded, Inc.
*/
+#include <linux/cleanup.h>
#include <linux/extcon-provider.h>
#include <linux/interrupt.h>
#include <linux/io.h>
@@ -118,7 +119,7 @@ struct rcar_gen3_chan {
struct regulator *vbus;
struct reset_control *rstc;
struct work_struct work;
- struct mutex lock; /* protects rphys[...].powered */
+ spinlock_t lock; /* protects access to hardware and driver data structure. */
enum usb_dr_mode dr_mode;
u32 obint_enable_bits;
bool extcon_host;
@@ -348,6 +349,8 @@ static ssize_t role_store(struct device *dev, struct device_attribute *attr,
bool is_b_device;
enum phy_mode cur_mode, new_mode;
+ guard(spinlock_irqsave)(&ch->lock);
+
if (!ch->is_otg_channel || !rcar_gen3_is_any_otg_rphy_initialized(ch))
return -EIO;
@@ -415,7 +418,7 @@ static void rcar_gen3_init_otg(struct rcar_gen3_chan *ch)
val = readl(usb2_base + USB2_ADPCTRL);
writel(val | USB2_ADPCTRL_IDPULLUP, usb2_base + USB2_ADPCTRL);
}
- msleep(20);
+ mdelay(20);
writel(0xffffffff, usb2_base + USB2_OBINTSTA);
writel(ch->obint_enable_bits, usb2_base + USB2_OBINTEN);
@@ -436,12 +439,14 @@ static irqreturn_t rcar_gen3_phy_usb2_irq(int irq, void *_ch)
if (pm_runtime_suspended(dev))
goto rpm_put;
- status = readl(usb2_base + USB2_OBINTSTA);
- if (status & ch->obint_enable_bits) {
- dev_vdbg(dev, "%s: %08x\n", __func__, status);
- writel(ch->obint_enable_bits, usb2_base + USB2_OBINTSTA);
- rcar_gen3_device_recognition(ch);
- ret = IRQ_HANDLED;
+ scoped_guard(spinlock, &ch->lock) {
+ status = readl(usb2_base + USB2_OBINTSTA);
+ if (status & ch->obint_enable_bits) {
+ dev_vdbg(dev, "%s: %08x\n", __func__, status);
+ writel(ch->obint_enable_bits, usb2_base + USB2_OBINTSTA);
+ rcar_gen3_device_recognition(ch);
+ ret = IRQ_HANDLED;
+ }
}
rpm_put:
@@ -456,6 +461,8 @@ static int rcar_gen3_phy_usb2_init(struct phy *p)
void __iomem *usb2_base = channel->base;
u32 val;
+ guard(spinlock_irqsave)(&channel->lock);
+
/* Initialize USB2 part */
val = readl(usb2_base + USB2_INT_ENABLE);
val |= USB2_INT_ENABLE_UCOM_INTEN | rphy->int_enable_bits;
@@ -479,6 +486,8 @@ static int rcar_gen3_phy_usb2_exit(struct phy *p)
void __iomem *usb2_base = channel->base;
u32 val;
+ guard(spinlock_irqsave)(&channel->lock);
+
rphy->initialized = false;
val = readl(usb2_base + USB2_INT_ENABLE);
@@ -498,16 +507,17 @@ static int rcar_gen3_phy_usb2_power_on(struct phy *p)
u32 val;
int ret = 0;
- mutex_lock(&channel->lock);
- if (!rcar_gen3_are_all_rphys_power_off(channel))
- goto out;
-
if (channel->vbus) {
ret = regulator_enable(channel->vbus);
if (ret)
- goto out;
+ return ret;
}
+ guard(spinlock_irqsave)(&channel->lock);
+
+ if (!rcar_gen3_are_all_rphys_power_off(channel))
+ goto out;
+
val = readl(usb2_base + USB2_USBCTR);
val |= USB2_USBCTR_PLL_RST;
writel(val, usb2_base + USB2_USBCTR);
@@ -517,7 +527,6 @@ static int rcar_gen3_phy_usb2_power_on(struct phy *p)
out:
/* The powered flag should be set for any other phys anyway */
rphy->powered = true;
- mutex_unlock(&channel->lock);
return 0;
}
@@ -528,18 +537,12 @@ static int rcar_gen3_phy_usb2_power_off(struct phy *p)
struct rcar_gen3_chan *channel = rphy->ch;
int ret = 0;
- mutex_lock(&channel->lock);
- rphy->powered = false;
-
- if (!rcar_gen3_are_all_rphys_power_off(channel))
- goto out;
+ scoped_guard(spinlock_irqsave, &channel->lock)
+ rphy->powered = false;
if (channel->vbus)
ret = regulator_disable(channel->vbus);
-out:
- mutex_unlock(&channel->lock);
-
return ret;
}
@@ -750,7 +753,7 @@ static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
if (phy_data->no_adp_ctrl)
channel->obint_enable_bits = USB2_OBINT_IDCHG_EN;
- mutex_init(&channel->lock);
+ spin_lock_init(&channel->lock);
for (i = 0; i < NUM_OF_PHYS; i++) {
channel->rphys[i].phy = devm_phy_create(dev, NULL,
phy_data->phy_usb2_ops);
--
2.43.0
The symlink body (->target) should be freed at the same time as the inode
itself per commit 4fdcfab5b553 ("jffs2: fix use-after-free on symlink
traversal"). It is a filesystem-specific field but there exist several
error paths during generic inode allocation when ->free_inode(), namely
jffs2_free_inode(), is called with still uninitialized private info.
The calltrace looks like:
alloc_inode
inode_init_always // fails
i_callback
free_inode
jffs2_free_inode // touches uninit ->target field
Commit af9a8730ddb6 ("jffs2: Fix potential illegal address access in
jffs2_free_inode") approached the observed problem but fixed it only
partially. Our local Syzkaller instance is still hitting these kinds of
failures.
The thing is that jffs2_i_init_once(), where the initialization of
f->target has been moved, is called once per slab allocation so it won't
be called for the object structure possibly retrieved later from the slab
cache for reuse.
The practice followed by many other filesystems is to initialize
filesystem-private inode contents in the corresponding ->alloc_inode()
callbacks. This also allows to drop initialization from jffs2_iget() and
jffs2_new_inode() as ->alloc_inode() is called in those places.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 4fdcfab5b553 ("jffs2: fix use-after-free on symlink traversal")
Cc: stable(a)vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin(a)ispras.ru>
---
fs/jffs2/fs.c | 2 --
fs/jffs2/super.c | 3 ++-
2 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index d175cccb7c55..85c4b273918f 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -271,7 +271,6 @@ struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
f = JFFS2_INODE_INFO(inode);
c = JFFS2_SB_INFO(inode->i_sb);
- jffs2_init_inode_info(f);
mutex_lock(&f->sem);
ret = jffs2_do_read_inode(c, f, inode->i_ino, &latest_node);
@@ -439,7 +438,6 @@ struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode, struct jffs2_r
return ERR_PTR(-ENOMEM);
f = JFFS2_INODE_INFO(inode);
- jffs2_init_inode_info(f);
mutex_lock(&f->sem);
memset(ri, 0, sizeof(*ri));
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index 4545f885c41e..b56ff63357f3 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -42,6 +42,8 @@ static struct inode *jffs2_alloc_inode(struct super_block *sb)
f = alloc_inode_sb(sb, jffs2_inode_cachep, GFP_KERNEL);
if (!f)
return NULL;
+
+ jffs2_init_inode_info(f);
return &f->vfs_inode;
}
@@ -58,7 +60,6 @@ static void jffs2_i_init_once(void *foo)
struct jffs2_inode_info *f = foo;
mutex_init(&f->sem);
- f->target = NULL;
inode_init_once(&f->vfs_inode);
}
--
2.39.5
From: Steven Rostedt <rostedt(a)goodmis.org>
When the last fprobe is removed, it calls unregister_ftrace_graph() to
remove the graph_ops from function graph. The issue is when it does so, it
calls return before removing the function from its graph ops via
ftrace_set_filter_ips(). This leaves the last function lingering in the
fprobe's fgraph ops and if a probe is added it also enables that last
function (even though the callback will just drop it, it does add unneeded
overhead to make that call).
# echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# echo "f:myevent2 schedule_timeout" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
schedule_timeout (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# > /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
# echo "f:myevent3 kmem_cache_free" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kmem_cache_free (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
schedule_timeout (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
The above enabled a fprobe on kernel_clone, and then on schedule_timeout.
The content of the enabled_functions shows the functions that have a
callback attached to them. The fprobe attached to those functions
properly. Then the fprobes were cleared, and enabled_functions was empty
after that. But after adding a fprobe on kmem_cache_free, the
enabled_functions shows that the schedule_timeout was attached again. This
is because it was still left in the fprobe ops that is used to tell
function graph what functions it wants callbacks from.
Cc: stable(a)vger.kernel.org
Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org>
---
kernel/trace/fprobe.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 90241091ca61..886090845b1a 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -403,11 +403,9 @@ static void fprobe_graph_remove_ips(unsigned long *addrs, int num)
lockdep_assert_held(&fprobe_mutex);
fprobe_graph_active--;
- if (!fprobe_graph_active) {
- /* Q: should we unregister it ? */
+ /* Q: should we unregister it ? */
+ if (!fprobe_graph_active)
unregister_ftrace_graph(&fprobe_graph_ops);
- return;
- }
ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0);
}
--
2.47.2
From: Steven Rostedt <rostedt(a)goodmis.org>
When adding a new fprobe, it will update the function hash to the
functions the fprobe is attached to and register with function graph to
have it call the registered functions. The fprobe_graph_active variable
keeps track of the number of fprobes that are using function graph.
If two fprobes attach to the same function, it increments the
fprobe_graph_active for each of them. But when they are removed, the first
fprobe to be removed will see that the function it is attached to is also
used by another fprobe and it will not remove that function from
function_graph. The logic will skip decrementing the fprobe_graph_active
variable.
This causes the fprobe_graph_active variable to not go to zero when all
fprobes are removed, and in doing so it does not unregister from
function graph. As the fgraph ops hash will now be empty, and an empty
filter hash means all functions are enabled, this triggers function graph
to add a callback to the fprobe infrastructure for every function!
# echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events
# echo "f:myevent2 kernel_clone%return" >> /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
kernel_clone (1) tramp: 0xffffffffc0024000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60
# > /sys/kernel/tracing/dynamic_events
# cat /sys/kernel/tracing/enabled_functions
trace_initcall_start_cb (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
try_to_run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
x86_pmu_show_pmu_cap (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
cleanup_rapl_pmus (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_free_pcibus_map (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_types_exit (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
uncore_pci_exit.part.0 (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
kvm_shutdown (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
vmx_dump_msrs (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170
[..]
# cat /sys/kernel/tracing/enabled_functions | wc -l
54702
If a fprobe is being removed and all its functions are also traced by
other fprobes, still decrement the fprobe_graph_active counter.
Cc: stable(a)vger.kernel.org
Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
Closes: https://lore.kernel.org/all/20250217114918.10397-A-hca@linux.ibm.com/
Reported-by: Heiko Carstens <hca(a)linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org>
---
kernel/trace/fprobe.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index 2560b312ad57..90241091ca61 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -681,6 +681,8 @@ int unregister_fprobe(struct fprobe *fp)
if (count)
fprobe_graph_remove_ips(addrs, count);
+ else
+ fprobe_graph_active--;
kfree_rcu(hlist_array, rcu);
fp->hlist_array = NULL;
--
2.47.2