[Public]
Hi,
Rajib recently found that GPU reset is failing on DCN 3.1.4 with 6.1.y.
It's because of some missing commits in 6.1.y that skip the appropriate functions to match the GPU's graphics architecture. Backporting these and GPU reset works again.
Can you please bring these back to 6.1.y and 6.2.y?
2a7798ea7390 ("drm/amdgpu: for S0ix, skip SDMA 5.x+ suspend/resume")
e11c775030c5 ("drm/amdgpu: skip psp suspend for IMU enabled ASICs mode2 reset")
Thanks,
[Public]
Hi,
There is a bug present in 6.2.y and 6.1.y where if a dock that supports MST is unplugged during suspend it's not possible to get MST working after resume. This is because the cleanup/error path doesn't actually clear the MST tree.
It's fixed in 6.3 with:
3f6752b4de41 ("drm/amd/display: Clear MST topology if it fails to resume")
Can this please be backported to 6.2.y and 6.1.y?
Thanks,
Please take 84aca0a7e039 ("blk-throttle: Fix that bps of child could
exceed bps limited in parent") for stable 6.1
Cherry pick claims that the patch applies cleanly to previous trees.
Don't believe it. This fixes a regression introduced in 5.18 abouts
The patch below does not apply to the 6.2-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-6.2.y
git checkout FETCH_HEAD
git cherry-pick -x 3dd4432549415f3c65dd52d5c687629efbf4ece1
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041140-childcare-profusely-9882@gregkh' --subject-prefix 'PATCH 6.2.y' HEAD^..
Possible dependencies:
3dd443254941 ("mm: enable maple tree RCU mode by default")
3b9dbd5e91b1 ("kernel/fork: convert forking to using the vmi iterator")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3dd4432549415f3c65dd52d5c687629efbf4ece1 Mon Sep 17 00:00:00 2001
From: "Liam R. Howlett" <Liam.Howlett(a)oracle.com>
Date: Mon, 27 Feb 2023 09:36:07 -0800
Subject: [PATCH] mm: enable maple tree RCU mode by default
Use the maple tree in RCU mode for VMA tracking.
The maple tree tracks the stack and is able to update the pivot
(lower/upper boundary) in-place to allow the page fault handler to write
to the tree while holding just the mmap read lock. This is safe as the
writes to the stack have a guard VMA which ensures there will always be a
NULL in the direction of the growth and thus will only update a pivot.
It is possible, but not recommended, to have VMAs that grow up/down
without guard VMAs. syzbot has constructed a testcase which sets up a VMA
to grow and consume the empty space. Overwriting the entire NULL entry
causes the tree to be altered in a way that is not safe for concurrent
readers; the readers may see a node being rewritten or one that does not
match the maple state they are using.
Enabling RCU mode allows the concurrent readers to see a stable node and
will return the expected result.
[Liam.Howlett(a)Oracle.com: we don't need to free the nodes with RCU[
Link: https://lore.kernel.org/linux-mm/000000000000b0a65805f663ace6@google.com/
Link: https://lkml.kernel.org/r/20230227173632.3292573-9-surenb@google.com
Fixes: d4af56c5c7c6 ("mm: start tracking VMAs with maple tree")
Signed-off-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb(a)google.com>
Reported-by: syzbot+8d95422d3537159ca390(a)syzkaller.appspotmail.com
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 0722859c3647..a57e6ae78e65 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -774,7 +774,8 @@ struct mm_struct {
unsigned long cpu_bitmap[];
};
-#define MM_MT_FLAGS (MT_FLAGS_ALLOC_RANGE | MT_FLAGS_LOCK_EXTERN)
+#define MM_MT_FLAGS (MT_FLAGS_ALLOC_RANGE | MT_FLAGS_LOCK_EXTERN | \
+ MT_FLAGS_USE_RCU)
extern struct mm_struct init_mm;
/* Pointer magic because the dynamic array size confuses some compilers. */
diff --git a/kernel/fork.c b/kernel/fork.c
index c0257cbee093..0c92f224c68c 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -617,6 +617,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
if (retval)
goto out;
+ mt_clear_in_rcu(vmi.mas.tree);
for_each_vma(old_vmi, mpnt) {
struct file *file;
@@ -700,6 +701,8 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
retval = arch_dup_mmap(oldmm, mm);
loop_out:
vma_iter_free(&vmi);
+ if (!retval)
+ mt_set_in_rcu(vmi.mas.tree);
out:
mmap_write_unlock(mm);
flush_tlb_mm(oldmm);
diff --git a/mm/mmap.c b/mm/mmap.c
index ad499f7b767f..ff68a67a2a7c 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2277,7 +2277,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
int count = 0;
int error = -ENOMEM;
MA_STATE(mas_detach, &mt_detach, 0, 0);
- mt_init_flags(&mt_detach, MT_FLAGS_LOCK_EXTERN);
+ mt_init_flags(&mt_detach, vmi->mas.tree->ma_flags & MT_FLAGS_LOCK_MASK);
mt_set_external_lock(&mt_detach, &mm->mmap_lock);
/*
@@ -3037,6 +3037,7 @@ void exit_mmap(struct mm_struct *mm)
*/
set_bit(MMF_OOM_SKIP, &mm->flags);
mmap_write_lock(mm);
+ mt_clear_in_rcu(&mm->mm_mt);
free_pgtables(&tlb, &mm->mm_mt, vma, FIRST_USER_ADDRESS,
USER_PGTABLES_CEILING);
tlb_finish_mmu(&tlb);
The patch below does not apply to the 6.1-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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 3dd4432549415f3c65dd52d5c687629efbf4ece1
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041138-delay-translate-7f35@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
3dd443254941 ("mm: enable maple tree RCU mode by default")
3b9dbd5e91b1 ("kernel/fork: convert forking to using the vmi iterator")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3dd4432549415f3c65dd52d5c687629efbf4ece1 Mon Sep 17 00:00:00 2001
From: "Liam R. Howlett" <Liam.Howlett(a)oracle.com>
Date: Mon, 27 Feb 2023 09:36:07 -0800
Subject: [PATCH] mm: enable maple tree RCU mode by default
Use the maple tree in RCU mode for VMA tracking.
The maple tree tracks the stack and is able to update the pivot
(lower/upper boundary) in-place to allow the page fault handler to write
to the tree while holding just the mmap read lock. This is safe as the
writes to the stack have a guard VMA which ensures there will always be a
NULL in the direction of the growth and thus will only update a pivot.
It is possible, but not recommended, to have VMAs that grow up/down
without guard VMAs. syzbot has constructed a testcase which sets up a VMA
to grow and consume the empty space. Overwriting the entire NULL entry
causes the tree to be altered in a way that is not safe for concurrent
readers; the readers may see a node being rewritten or one that does not
match the maple state they are using.
Enabling RCU mode allows the concurrent readers to see a stable node and
will return the expected result.
[Liam.Howlett(a)Oracle.com: we don't need to free the nodes with RCU[
Link: https://lore.kernel.org/linux-mm/000000000000b0a65805f663ace6@google.com/
Link: https://lkml.kernel.org/r/20230227173632.3292573-9-surenb@google.com
Fixes: d4af56c5c7c6 ("mm: start tracking VMAs with maple tree")
Signed-off-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb(a)google.com>
Reported-by: syzbot+8d95422d3537159ca390(a)syzkaller.appspotmail.com
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 0722859c3647..a57e6ae78e65 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -774,7 +774,8 @@ struct mm_struct {
unsigned long cpu_bitmap[];
};
-#define MM_MT_FLAGS (MT_FLAGS_ALLOC_RANGE | MT_FLAGS_LOCK_EXTERN)
+#define MM_MT_FLAGS (MT_FLAGS_ALLOC_RANGE | MT_FLAGS_LOCK_EXTERN | \
+ MT_FLAGS_USE_RCU)
extern struct mm_struct init_mm;
/* Pointer magic because the dynamic array size confuses some compilers. */
diff --git a/kernel/fork.c b/kernel/fork.c
index c0257cbee093..0c92f224c68c 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -617,6 +617,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
if (retval)
goto out;
+ mt_clear_in_rcu(vmi.mas.tree);
for_each_vma(old_vmi, mpnt) {
struct file *file;
@@ -700,6 +701,8 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
retval = arch_dup_mmap(oldmm, mm);
loop_out:
vma_iter_free(&vmi);
+ if (!retval)
+ mt_set_in_rcu(vmi.mas.tree);
out:
mmap_write_unlock(mm);
flush_tlb_mm(oldmm);
diff --git a/mm/mmap.c b/mm/mmap.c
index ad499f7b767f..ff68a67a2a7c 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2277,7 +2277,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
int count = 0;
int error = -ENOMEM;
MA_STATE(mas_detach, &mt_detach, 0, 0);
- mt_init_flags(&mt_detach, MT_FLAGS_LOCK_EXTERN);
+ mt_init_flags(&mt_detach, vmi->mas.tree->ma_flags & MT_FLAGS_LOCK_MASK);
mt_set_external_lock(&mt_detach, &mm->mmap_lock);
/*
@@ -3037,6 +3037,7 @@ void exit_mmap(struct mm_struct *mm)
*/
set_bit(MMF_OOM_SKIP, &mm->flags);
mmap_write_lock(mm);
+ mt_clear_in_rcu(&mm->mm_mt);
free_pgtables(&tlb, &mm->mm_mt, vma, FIRST_USER_ADDRESS,
USER_PGTABLES_CEILING);
tlb_finish_mmu(&tlb);
The patch below does not apply to the 6.2-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-6.2.y
git checkout FETCH_HEAD
git cherry-pick -x 0a2b18d948838e16912b3b627b504ab062b7d02a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041133-corroding-underdone-8e9f@gregkh' --subject-prefix 'PATCH 6.2.y' HEAD^..
Possible dependencies:
0a2b18d94883 ("maple_tree: add smp_rmb() to dead node detection")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 0a2b18d948838e16912b3b627b504ab062b7d02a Mon Sep 17 00:00:00 2001
From: "Liam R. Howlett" <Liam.Howlett(a)oracle.com>
Date: Mon, 27 Feb 2023 09:36:05 -0800
Subject: [PATCH] maple_tree: add smp_rmb() to dead node detection
Add an smp_rmb() before reading the parent pointer to ensure that anything
read from the node prior to the parent pointer hasn't been reordered ahead
of this check.
The is necessary for RCU mode.
Link: https://lkml.kernel.org/r/20230227173632.3292573-7-surenb@google.com
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 5202d89ba56e..72c89eb03393 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -539,9 +539,11 @@ static inline struct maple_node *mte_parent(const struct maple_enode *enode)
*/
static inline bool ma_dead_node(const struct maple_node *node)
{
- struct maple_node *parent = (void *)((unsigned long)
- node->parent & ~MAPLE_NODE_MASK);
+ struct maple_node *parent;
+ /* Do not reorder reads from the node prior to the parent check */
+ smp_rmb();
+ parent = (void *)((unsigned long) node->parent & ~MAPLE_NODE_MASK);
return (parent == node);
}
@@ -556,6 +558,8 @@ static inline bool mte_dead_node(const struct maple_enode *enode)
struct maple_node *parent, *node;
node = mte_to_node(enode);
+ /* Do not reorder reads from the node prior to the parent check */
+ smp_rmb();
parent = mte_parent(enode);
return (parent == node);
}
The patch below does not apply to the 6.1-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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 0a2b18d948838e16912b3b627b504ab062b7d02a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023041132-hundredth-delouse-b680@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
0a2b18d94883 ("maple_tree: add smp_rmb() to dead node detection")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 0a2b18d948838e16912b3b627b504ab062b7d02a Mon Sep 17 00:00:00 2001
From: "Liam R. Howlett" <Liam.Howlett(a)oracle.com>
Date: Mon, 27 Feb 2023 09:36:05 -0800
Subject: [PATCH] maple_tree: add smp_rmb() to dead node detection
Add an smp_rmb() before reading the parent pointer to ensure that anything
read from the node prior to the parent pointer hasn't been reordered ahead
of this check.
The is necessary for RCU mode.
Link: https://lkml.kernel.org/r/20230227173632.3292573-7-surenb@google.com
Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 5202d89ba56e..72c89eb03393 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -539,9 +539,11 @@ static inline struct maple_node *mte_parent(const struct maple_enode *enode)
*/
static inline bool ma_dead_node(const struct maple_node *node)
{
- struct maple_node *parent = (void *)((unsigned long)
- node->parent & ~MAPLE_NODE_MASK);
+ struct maple_node *parent;
+ /* Do not reorder reads from the node prior to the parent check */
+ smp_rmb();
+ parent = (void *)((unsigned long) node->parent & ~MAPLE_NODE_MASK);
return (parent == node);
}
@@ -556,6 +558,8 @@ static inline bool mte_dead_node(const struct maple_enode *enode)
struct maple_node *parent, *node;
node = mte_to_node(enode);
+ /* Do not reorder reads from the node prior to the parent check */
+ smp_rmb();
parent = mte_parent(enode);
return (parent == node);
}