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 7ca52541c05c832d32b112274f81a985101f9ba8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062026-stinger-coeditor-bb58@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7ca52541c05c832d32b112274f81a985101f9ba8 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet(a)google.com>
Date: Wed, 11 Jun 2025 08:35:01 +0000
Subject: [PATCH] net_sched: sch_sfq: reject invalid perturb period
Gerrard Tai reported that SFQ perturb_period has no range check yet,
and this can be used to trigger a race condition fixed in a separate patch.
We want to make sure ctl->perturb_period * HZ will not overflow
and is positive.
Tested:
tc qd add dev lo root sfq perturb -10 # negative value : error
Error: sch_sfq: invalid perturb period.
tc qd add dev lo root sfq perturb 1000000000 # too big : error
Error: sch_sfq: invalid perturb period.
tc qd add dev lo root sfq perturb 2000000 # acceptable value
tc -s -d qd sh dev lo
qdisc sfq 8005: root refcnt 2 limit 127p quantum 64Kb depth 127 flows 128 divisor 1024 perturb 2000000sec
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Gerrard Tai <gerrard.tai(a)starlabs.sg>
Signed-off-by: Eric Dumazet <edumazet(a)google.com>
Cc: stable(a)vger.kernel.org
Link: https://patch.msgid.link/20250611083501.1810459-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index 77fa02f2bfcd..a8cca549b5a2 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -656,6 +656,14 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt,
NL_SET_ERR_MSG_MOD(extack, "invalid quantum");
return -EINVAL;
}
+
+ if (ctl->perturb_period < 0 ||
+ ctl->perturb_period > INT_MAX / HZ) {
+ NL_SET_ERR_MSG_MOD(extack, "invalid perturb period");
+ return -EINVAL;
+ }
+ perturb_period = ctl->perturb_period * HZ;
+
if (ctl_v1 && !red_check_params(ctl_v1->qth_min, ctl_v1->qth_max,
ctl_v1->Wlog, ctl_v1->Scell_log, NULL))
return -EINVAL;
@@ -672,14 +680,12 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt,
headdrop = q->headdrop;
maxdepth = q->maxdepth;
maxflows = q->maxflows;
- perturb_period = q->perturb_period;
quantum = q->quantum;
flags = q->flags;
/* update and validate configuration */
if (ctl->quantum)
quantum = ctl->quantum;
- perturb_period = ctl->perturb_period * HZ;
if (ctl->flows)
maxflows = min_t(u32, ctl->flows, SFQ_MAX_FLOWS);
if (ctl->divisor) {
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 66d590b828b1fd9fa337047ae58fe1c4c6f43609
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062054-luminance-hacker-c550@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 66d590b828b1fd9fa337047ae58fe1c4c6f43609 Mon Sep 17 00:00:00 2001
From: Shyam Prasad N <sprasad(a)microsoft.com>
Date: Mon, 2 Jun 2025 22:37:12 +0530
Subject: [PATCH] cifs: deal with the channel loading lag while picking
channels
Our current approach to select a channel for sending requests is this:
1. iterate all channels to find the min and max queue depth
2. if min and max are not the same, pick the channel with min depth
3. if min and max are same, round robin, as all channels are equally loaded
The problem with this approach is that there's a lag between selecting
a channel and sending the request (that increases the queue depth on the channel).
While these numbers will eventually catch up, there could be a skew in the
channel usage, depending on the application's I/O parallelism and the server's
speed of handling requests.
With sufficient parallelism, this lag can artificially increase the queue depth,
thereby impacting the performance negatively.
This change will change the step 1 above to start the iteration from the last
selected channel. This is to reduce the skew in channel usage even in the presence
of this lag.
Fixes: ea90708d3cf3 ("cifs: use the least loaded channel for sending requests")
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Shyam Prasad N <sprasad(a)microsoft.com>
Signed-off-by: Steve French <stfrench(a)microsoft.com>
diff --git a/fs/smb/client/transport.c b/fs/smb/client/transport.c
index 266af17aa7d9..191783f553ce 100644
--- a/fs/smb/client/transport.c
+++ b/fs/smb/client/transport.c
@@ -1018,14 +1018,16 @@ struct TCP_Server_Info *cifs_pick_channel(struct cifs_ses *ses)
uint index = 0;
unsigned int min_in_flight = UINT_MAX, max_in_flight = 0;
struct TCP_Server_Info *server = NULL;
- int i;
+ int i, start, cur;
if (!ses)
return NULL;
spin_lock(&ses->chan_lock);
+ start = atomic_inc_return(&ses->chan_seq);
for (i = 0; i < ses->chan_count; i++) {
- server = ses->chans[i].server;
+ cur = (start + i) % ses->chan_count;
+ server = ses->chans[cur].server;
if (!server || server->terminate)
continue;
@@ -1042,17 +1044,15 @@ struct TCP_Server_Info *cifs_pick_channel(struct cifs_ses *ses)
*/
if (server->in_flight < min_in_flight) {
min_in_flight = server->in_flight;
- index = i;
+ index = cur;
}
if (server->in_flight > max_in_flight)
max_in_flight = server->in_flight;
}
/* if all channels are equally loaded, fall back to round-robin */
- if (min_in_flight == max_in_flight) {
- index = (uint)atomic_inc_return(&ses->chan_seq);
- index %= ses->chan_count;
- }
+ if (min_in_flight == max_in_flight)
+ index = (uint)start % ses->chan_count;
server = ses->chans[index].server;
spin_unlock(&ses->chan_lock);
Hi,
I have discovered that two small form factor desktops with Ryzen AI 7
350 and Ryzen AI 5 340 crash when woken up from suspend. I can see how
the LED on the USB mouse is switched on when I trigger a resume via
keyboard button, but the display remains black. The kernel also no
longer responds to Magic SysRq keys in this state.
The problem affects all kernels after merge b50753547453 (v6.11.0). But
this merge only adds PCI_DEVICE_ID_AMD_1AH_M60H_ROOT with commit
59c34008d (necessary to trigger this bug with Ryzen AI CPU).
I cherry-picked this commit and continued searching. Which finally led
me to commit f6098641d3e - drm/amd/display: fix s2idle entry for DCN3.5+
If I remove the code, which has changed somewhat in the meantime, then
the suspend works without any problems. See the following patch.
Regards,
Georg
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index d3100f641ac6..76204ae70acc 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -3121,9 +3121,6 @@ static int dm_suspend(struct amdgpu_ip_block
*ip_block)
dc_set_power_state(dm->dc, DC_ACPI_CM_POWER_STATE_D3);
- if (dm->dc->caps.ips_support && adev->in_s0ix)
- dc_allow_idle_optimizations(dm->dc, true);
-
dc_dmub_srv_set_power_state(dm->dc->ctx->dmub_srv,
DC_ACPI_CM_POWER_STATE_D3);
return 0;
When the PSLVERR_RESP_EN parameter is set to 1, the device generates
an error response if an attempt is made to read an empty RBR (Receive
Buffer Register) while the FIFO is enabled.
In serial8250_do_startup(), calling serial_port_out(port, UART_LCR,
UART_LCR_WLEN8) triggers dw8250_check_lcr(), which invokes
dw8250_force_idle() and serial8250_clear_and_reinit_fifos(). The latter
function enables the FIFO via serial_out(p, UART_FCR, p->fcr).
Execution proceeds to the serial_port_in(port, UART_RX).
This satisfies the PSLVERR trigger condition.
When another CPU (e.g., using printk()) is accessing the UART (UART
is busy), the current CPU fails the check (value & ~UART_LCR_SPAR) ==
(lcr & ~UART_LCR_SPAR) in dw8250_check_lcr(), causing it to enter
dw8250_force_idle().
Put serial_port_out(port, UART_LCR, UART_LCR_WLEN8) under the port->lock
to fix this issue.
Panic backtrace:
[ 0.442336] Oops - unknown exception [#1]
[ 0.442343] epc : dw8250_serial_in32+0x1e/0x4a
[ 0.442351] ra : serial8250_do_startup+0x2c8/0x88e
...
[ 0.442416] console_on_rootfs+0x26/0x70
Fixes: c49436b657d0 ("serial: 8250_dw: Improve unwritable LCR workaround")
Link: https://lore.kernel.org/all/84cydt5peu.fsf@jogness.linutronix.de/T/
Signed-off-by: Yunhui Cui <cuiyunhui(a)bytedance.com>
Cc: stable(a)vger.kernel.org
---
drivers/tty/serial/8250/8250_port.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 6d7b8c4667c9c..07fe818dffa34 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2376,9 +2376,10 @@ int serial8250_do_startup(struct uart_port *port)
/*
* Now, initialize the UART
*/
- serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
uart_port_lock_irqsave(port, &flags);
+ serial_port_out(port, UART_LCR, UART_LCR_WLEN8);
+
if (up->port.flags & UPF_FOURPORT) {
if (!up->port.irq)
up->port.mctrl |= TIOCM_OUT1;
--
2.39.5
The patch below does not apply to the 6.15-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-6.15.y
git checkout FETCH_HEAD
git cherry-pick -x 595cf683519ab5a277d258a2251ee8cc7b838d6d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062039-policy-handheld-01c6@gregkh' --subject-prefix 'PATCH 6.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 595cf683519ab5a277d258a2251ee8cc7b838d6d Mon Sep 17 00:00:00 2001
From: Shivank Garg <shivankg(a)amd.com>
Date: Mon, 26 May 2025 18:28:18 +0000
Subject: [PATCH] mm/khugepaged: fix race with folio split/free using temporary
reference
hpage_collapse_scan_file() calls is_refcount_suitable(), which in turn
calls folio_mapcount(). folio_mapcount() checks folio_test_large() before
proceeding to folio_large_mapcount(), but there is a race window where the
folio may get split/freed between these checks, triggering:
VM_WARN_ON_FOLIO(!folio_test_large(folio), folio)
Take a temporary reference to the folio in hpage_collapse_scan_file().
This stabilizes the folio during refcount check and prevents incorrect
large folio detection due to concurrent split/free. Use helper
folio_expected_ref_count() + 1 to compare with folio_ref_count() instead
of using is_refcount_suitable().
Link: https://lkml.kernel.org/r/20250526182818.37978-1-shivankg@amd.com
Fixes: 05c5323b2a34 ("mm: track mapcount of large folios in single value")
Signed-off-by: Shivank Garg <shivankg(a)amd.com>
Reported-by: syzbot+2b99589e33edbe9475ca(a)syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6828470d.a70a0220.38f255.000c.GAE@google.com
Suggested-by: David Hildenbrand <david(a)redhat.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Acked-by: Dev Jain <dev.jain(a)arm.com>
Reviewed-by: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Cc: Bharata B Rao <bharata(a)amd.com>
Cc: Fengwei Yin <fengwei.yin(a)intel.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Mariano Pache <npache(a)redhat.com>
Cc: Ryan Roberts <ryan.roberts(a)arm.com>
Cc: Zi Yan <ziy(a)nvidia.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index cdf5a581368b..7731a162a1a7 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2293,6 +2293,17 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr,
continue;
}
+ if (!folio_try_get(folio)) {
+ xas_reset(&xas);
+ continue;
+ }
+
+ if (unlikely(folio != xas_reload(&xas))) {
+ folio_put(folio);
+ xas_reset(&xas);
+ continue;
+ }
+
if (folio_order(folio) == HPAGE_PMD_ORDER &&
folio->index == start) {
/* Maybe PMD-mapped */
@@ -2303,23 +2314,27 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr,
* it's safe to skip LRU and refcount checks before
* returning.
*/
+ folio_put(folio);
break;
}
node = folio_nid(folio);
if (hpage_collapse_scan_abort(node, cc)) {
result = SCAN_SCAN_ABORT;
+ folio_put(folio);
break;
}
cc->node_load[node]++;
if (!folio_test_lru(folio)) {
result = SCAN_PAGE_LRU;
+ folio_put(folio);
break;
}
- if (!is_refcount_suitable(folio)) {
+ if (folio_expected_ref_count(folio) + 1 != folio_ref_count(folio)) {
result = SCAN_PAGE_COUNT;
+ folio_put(folio);
break;
}
@@ -2331,6 +2346,7 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr,
*/
present += folio_nr_pages(folio);
+ folio_put(folio);
if (need_resched()) {
xas_pause(&xas);
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 1013af4f585fccc4d3e5c5824d174de2257f7d6d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062056-decree-conduit-b901@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1013af4f585fccc4d3e5c5824d174de2257f7d6d Mon Sep 17 00:00:00 2001
From: Jann Horn <jannh(a)google.com>
Date: Tue, 27 May 2025 23:23:54 +0200
Subject: [PATCH] mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race
huge_pmd_unshare() drops a reference on a page table that may have
previously been shared across processes, potentially turning it into a
normal page table used in another process in which unrelated VMAs can
afterwards be installed.
If this happens in the middle of a concurrent gup_fast(), gup_fast() could
end up walking the page tables of another process. While I don't see any
way in which that immediately leads to kernel memory corruption, it is
really weird and unexpected.
Fix it with an explicit broadcast IPI through tlb_remove_table_sync_one(),
just like we do in khugepaged when removing page tables for a THP
collapse.
Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-2-1329349bad1…
Link: https://lkml.kernel.org/r/20250527-hugetlb-fixes-splitrace-v1-2-f4136f5ec58…
Fixes: 39dde65c9940 ("[PATCH] shared page table for hugetlb page")
Signed-off-by: Jann Horn <jannh(a)google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Muchun Song <muchun.song(a)linux.dev>
Cc: Oscar Salvador <osalvador(a)suse.de>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7ba020d489d4..8746ed2fec13 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7629,6 +7629,13 @@ int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
return 0;
pud_clear(pud);
+ /*
+ * Once our caller drops the rmap lock, some other process might be
+ * using this page table as a normal, non-hugetlb page table.
+ * Wait for pending gup_fast() in other threads to finish before letting
+ * that happen.
+ */
+ tlb_remove_table_sync_one();
ptdesc_pmd_pts_dec(virt_to_ptdesc(ptep));
mm_dec_nr_pmds(mm);
return 1;
The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 1013af4f585fccc4d3e5c5824d174de2257f7d6d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062055-curator-nest-bade@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1013af4f585fccc4d3e5c5824d174de2257f7d6d Mon Sep 17 00:00:00 2001
From: Jann Horn <jannh(a)google.com>
Date: Tue, 27 May 2025 23:23:54 +0200
Subject: [PATCH] mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race
huge_pmd_unshare() drops a reference on a page table that may have
previously been shared across processes, potentially turning it into a
normal page table used in another process in which unrelated VMAs can
afterwards be installed.
If this happens in the middle of a concurrent gup_fast(), gup_fast() could
end up walking the page tables of another process. While I don't see any
way in which that immediately leads to kernel memory corruption, it is
really weird and unexpected.
Fix it with an explicit broadcast IPI through tlb_remove_table_sync_one(),
just like we do in khugepaged when removing page tables for a THP
collapse.
Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-2-1329349bad1…
Link: https://lkml.kernel.org/r/20250527-hugetlb-fixes-splitrace-v1-2-f4136f5ec58…
Fixes: 39dde65c9940 ("[PATCH] shared page table for hugetlb page")
Signed-off-by: Jann Horn <jannh(a)google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Muchun Song <muchun.song(a)linux.dev>
Cc: Oscar Salvador <osalvador(a)suse.de>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7ba020d489d4..8746ed2fec13 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7629,6 +7629,13 @@ int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
return 0;
pud_clear(pud);
+ /*
+ * Once our caller drops the rmap lock, some other process might be
+ * using this page table as a normal, non-hugetlb page table.
+ * Wait for pending gup_fast() in other threads to finish before letting
+ * that happen.
+ */
+ tlb_remove_table_sync_one();
ptdesc_pmd_pts_dec(virt_to_ptdesc(ptep));
mm_dec_nr_pmds(mm);
return 1;
The patch below does not apply to the 5.15-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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 1013af4f585fccc4d3e5c5824d174de2257f7d6d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062055-pettiness-snowshoe-2310@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1013af4f585fccc4d3e5c5824d174de2257f7d6d Mon Sep 17 00:00:00 2001
From: Jann Horn <jannh(a)google.com>
Date: Tue, 27 May 2025 23:23:54 +0200
Subject: [PATCH] mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race
huge_pmd_unshare() drops a reference on a page table that may have
previously been shared across processes, potentially turning it into a
normal page table used in another process in which unrelated VMAs can
afterwards be installed.
If this happens in the middle of a concurrent gup_fast(), gup_fast() could
end up walking the page tables of another process. While I don't see any
way in which that immediately leads to kernel memory corruption, it is
really weird and unexpected.
Fix it with an explicit broadcast IPI through tlb_remove_table_sync_one(),
just like we do in khugepaged when removing page tables for a THP
collapse.
Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-2-1329349bad1…
Link: https://lkml.kernel.org/r/20250527-hugetlb-fixes-splitrace-v1-2-f4136f5ec58…
Fixes: 39dde65c9940 ("[PATCH] shared page table for hugetlb page")
Signed-off-by: Jann Horn <jannh(a)google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Muchun Song <muchun.song(a)linux.dev>
Cc: Oscar Salvador <osalvador(a)suse.de>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7ba020d489d4..8746ed2fec13 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7629,6 +7629,13 @@ int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
return 0;
pud_clear(pud);
+ /*
+ * Once our caller drops the rmap lock, some other process might be
+ * using this page table as a normal, non-hugetlb page table.
+ * Wait for pending gup_fast() in other threads to finish before letting
+ * that happen.
+ */
+ tlb_remove_table_sync_one();
ptdesc_pmd_pts_dec(virt_to_ptdesc(ptep));
mm_dec_nr_pmds(mm);
return 1;
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 1013af4f585fccc4d3e5c5824d174de2257f7d6d
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062054-snowdrop-stitch-3abf@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1013af4f585fccc4d3e5c5824d174de2257f7d6d Mon Sep 17 00:00:00 2001
From: Jann Horn <jannh(a)google.com>
Date: Tue, 27 May 2025 23:23:54 +0200
Subject: [PATCH] mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race
huge_pmd_unshare() drops a reference on a page table that may have
previously been shared across processes, potentially turning it into a
normal page table used in another process in which unrelated VMAs can
afterwards be installed.
If this happens in the middle of a concurrent gup_fast(), gup_fast() could
end up walking the page tables of another process. While I don't see any
way in which that immediately leads to kernel memory corruption, it is
really weird and unexpected.
Fix it with an explicit broadcast IPI through tlb_remove_table_sync_one(),
just like we do in khugepaged when removing page tables for a THP
collapse.
Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-2-1329349bad1…
Link: https://lkml.kernel.org/r/20250527-hugetlb-fixes-splitrace-v1-2-f4136f5ec58…
Fixes: 39dde65c9940 ("[PATCH] shared page table for hugetlb page")
Signed-off-by: Jann Horn <jannh(a)google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Muchun Song <muchun.song(a)linux.dev>
Cc: Oscar Salvador <osalvador(a)suse.de>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7ba020d489d4..8746ed2fec13 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -7629,6 +7629,13 @@ int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma,
return 0;
pud_clear(pud);
+ /*
+ * Once our caller drops the rmap lock, some other process might be
+ * using this page table as a normal, non-hugetlb page table.
+ * Wait for pending gup_fast() in other threads to finish before letting
+ * that happen.
+ */
+ tlb_remove_table_sync_one();
ptdesc_pmd_pts_dec(virt_to_ptdesc(ptep));
mm_dec_nr_pmds(mm);
return 1;
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 081056dc00a27bccb55ccc3c6f230a3d5fd3f7e0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062044-sporty-zesty-9142@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 081056dc00a27bccb55ccc3c6f230a3d5fd3f7e0 Mon Sep 17 00:00:00 2001
From: Jann Horn <jannh(a)google.com>
Date: Tue, 27 May 2025 23:23:53 +0200
Subject: [PATCH] mm/hugetlb: unshare page tables during VMA split, not before
Currently, __split_vma() triggers hugetlb page table unsharing through
vm_ops->may_split(). This happens before the VMA lock and rmap locks are
taken - which is too early, it allows racing VMA-locked page faults in our
process and racing rmap walks from other processes to cause page tables to
be shared again before we actually perform the split.
Fix it by explicitly calling into the hugetlb unshare logic from
__split_vma() in the same place where THP splitting also happens. At that
point, both the VMA and the rmap(s) are write-locked.
An annoying detail is that we can now call into the helper
hugetlb_unshare_pmds() from two different locking contexts:
1. from hugetlb_split(), holding:
- mmap lock (exclusively)
- VMA lock
- file rmap lock (exclusively)
2. hugetlb_unshare_all_pmds(), which I think is designed to be able to
call us with only the mmap lock held (in shared mode), but currently
only runs while holding mmap lock (exclusively) and VMA lock
Backporting note:
This commit fixes a racy protection that was introduced in commit
b30c14cd6102 ("hugetlb: unshare some PMDs when splitting VMAs"); that
commit claimed to fix an issue introduced in 5.13, but it should actually
also go all the way back.
[jannh(a)google.com: v2]
Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-1-1329349bad1…
Link: https://lkml.kernel.org/r/20250528-hugetlb-fixes-splitrace-v2-0-1329349bad1…
Link: https://lkml.kernel.org/r/20250527-hugetlb-fixes-splitrace-v1-1-f4136f5ec58…
Fixes: 39dde65c9940 ("[PATCH] shared page table for hugetlb page")
Signed-off-by: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Oscar Salvador <osalvador(a)suse.de>
Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org> [b30c14cd6102: hugetlb: unshare some PMDs when splitting VMAs]
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 0598f36931de..42f374e828a2 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -279,6 +279,7 @@ bool is_hugetlb_entry_migration(pte_t pte);
bool is_hugetlb_entry_hwpoisoned(pte_t pte);
void hugetlb_unshare_all_pmds(struct vm_area_struct *vma);
void fixup_hugetlb_reservations(struct vm_area_struct *vma);
+void hugetlb_split(struct vm_area_struct *vma, unsigned long addr);
#else /* !CONFIG_HUGETLB_PAGE */
@@ -476,6 +477,8 @@ static inline void fixup_hugetlb_reservations(struct vm_area_struct *vma)
{
}
+static inline void hugetlb_split(struct vm_area_struct *vma, unsigned long addr) {}
+
#endif /* !CONFIG_HUGETLB_PAGE */
#ifndef pgd_write
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index f0b1d53079f9..7ba020d489d4 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -121,7 +121,7 @@ static void hugetlb_vma_lock_free(struct vm_area_struct *vma);
static void hugetlb_vma_lock_alloc(struct vm_area_struct *vma);
static void __hugetlb_vma_unlock_write_free(struct vm_area_struct *vma);
static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
- unsigned long start, unsigned long end);
+ unsigned long start, unsigned long end, bool take_locks);
static struct resv_map *vma_resv_map(struct vm_area_struct *vma);
static void hugetlb_free_folio(struct folio *folio)
@@ -5426,26 +5426,40 @@ static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr)
{
if (addr & ~(huge_page_mask(hstate_vma(vma))))
return -EINVAL;
+ return 0;
+}
+void hugetlb_split(struct vm_area_struct *vma, unsigned long addr)
+{
/*
* PMD sharing is only possible for PUD_SIZE-aligned address ranges
* in HugeTLB VMAs. If we will lose PUD_SIZE alignment due to this
* split, unshare PMDs in the PUD_SIZE interval surrounding addr now.
+ * This function is called in the middle of a VMA split operation, with
+ * MM, VMA and rmap all write-locked to prevent concurrent page table
+ * walks (except hardware and gup_fast()).
*/
+ vma_assert_write_locked(vma);
+ i_mmap_assert_write_locked(vma->vm_file->f_mapping);
+
if (addr & ~PUD_MASK) {
- /*
- * hugetlb_vm_op_split is called right before we attempt to
- * split the VMA. We will need to unshare PMDs in the old and
- * new VMAs, so let's unshare before we split.
- */
unsigned long floor = addr & PUD_MASK;
unsigned long ceil = floor + PUD_SIZE;
- if (floor >= vma->vm_start && ceil <= vma->vm_end)
- hugetlb_unshare_pmds(vma, floor, ceil);
+ if (floor >= vma->vm_start && ceil <= vma->vm_end) {
+ /*
+ * Locking:
+ * Use take_locks=false here.
+ * The file rmap lock is already held.
+ * The hugetlb VMA lock can't be taken when we already
+ * hold the file rmap lock, and we don't need it because
+ * its purpose is to synchronize against concurrent page
+ * table walks, which are not possible thanks to the
+ * locks held by our caller.
+ */
+ hugetlb_unshare_pmds(vma, floor, ceil, /* take_locks = */ false);
+ }
}
-
- return 0;
}
static unsigned long hugetlb_vm_op_pagesize(struct vm_area_struct *vma)
@@ -7885,9 +7899,16 @@ void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int re
spin_unlock_irq(&hugetlb_lock);
}
+/*
+ * If @take_locks is false, the caller must ensure that no concurrent page table
+ * access can happen (except for gup_fast() and hardware page walks).
+ * If @take_locks is true, we take the hugetlb VMA lock (to lock out things like
+ * concurrent page fault handling) and the file rmap lock.
+ */
static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
unsigned long start,
- unsigned long end)
+ unsigned long end,
+ bool take_locks)
{
struct hstate *h = hstate_vma(vma);
unsigned long sz = huge_page_size(h);
@@ -7911,8 +7932,12 @@ static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm,
start, end);
mmu_notifier_invalidate_range_start(&range);
- hugetlb_vma_lock_write(vma);
- i_mmap_lock_write(vma->vm_file->f_mapping);
+ if (take_locks) {
+ hugetlb_vma_lock_write(vma);
+ i_mmap_lock_write(vma->vm_file->f_mapping);
+ } else {
+ i_mmap_assert_write_locked(vma->vm_file->f_mapping);
+ }
for (address = start; address < end; address += PUD_SIZE) {
ptep = hugetlb_walk(vma, address, sz);
if (!ptep)
@@ -7922,8 +7947,10 @@ static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
spin_unlock(ptl);
}
flush_hugetlb_tlb_range(vma, start, end);
- i_mmap_unlock_write(vma->vm_file->f_mapping);
- hugetlb_vma_unlock_write(vma);
+ if (take_locks) {
+ i_mmap_unlock_write(vma->vm_file->f_mapping);
+ hugetlb_vma_unlock_write(vma);
+ }
/*
* No need to call mmu_notifier_arch_invalidate_secondary_tlbs(), see
* Documentation/mm/mmu_notifier.rst.
@@ -7938,7 +7965,8 @@ static void hugetlb_unshare_pmds(struct vm_area_struct *vma,
void hugetlb_unshare_all_pmds(struct vm_area_struct *vma)
{
hugetlb_unshare_pmds(vma, ALIGN(vma->vm_start, PUD_SIZE),
- ALIGN_DOWN(vma->vm_end, PUD_SIZE));
+ ALIGN_DOWN(vma->vm_end, PUD_SIZE),
+ /* take_locks = */ true);
}
/*
diff --git a/mm/vma.c b/mm/vma.c
index 1c6595f282e5..7ebc9eb608f4 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -539,7 +539,14 @@ __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma,
init_vma_prep(&vp, vma);
vp.insert = new;
vma_prepare(&vp);
+
+ /*
+ * Get rid of huge pages and shared page tables straddling the split
+ * boundary.
+ */
vma_adjust_trans_huge(vma, vma->vm_start, addr, NULL);
+ if (is_vm_hugetlb_page(vma))
+ hugetlb_split(vma, addr);
if (new_below) {
vma->vm_start = addr;
diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h
index 441feb21aa5a..4505b1c31be1 100644
--- a/tools/testing/vma/vma_internal.h
+++ b/tools/testing/vma/vma_internal.h
@@ -932,6 +932,8 @@ static inline void vma_adjust_trans_huge(struct vm_area_struct *vma,
(void)next;
}
+static inline void hugetlb_split(struct vm_area_struct *, unsigned long) {}
+
static inline void vma_iter_free(struct vma_iterator *vmi)
{
mas_destroy(&vmi->mas);
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 2b12d06c37fd3a394376f42f026a7478d826ed63
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062015-email-sulphuric-0b7f@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2b12d06c37fd3a394376f42f026a7478d826ed63 Mon Sep 17 00:00:00 2001
From: Pu Lehui <pulehui(a)huawei.com>
Date: Thu, 29 May 2025 15:56:47 +0000
Subject: [PATCH] mm: fix uprobe pte be overwritten when expanding vma
Patch series "Fix uprobe pte be overwritten when expanding vma".
This patch (of 4):
We encountered a BUG alert triggered by Syzkaller as follows:
BUG: Bad rss-counter state mm:00000000b4a60fca type:MM_ANONPAGES val:1
And we can reproduce it with the following steps:
1. register uprobe on file at zero offset
2. mmap the file at zero offset:
addr1 = mmap(NULL, 2 * 4096, PROT_NONE, MAP_PRIVATE, fd, 0);
3. mremap part of vma1 to new vma2:
addr2 = mremap(addr1, 4096, 2 * 4096, MREMAP_MAYMOVE);
4. mremap back to orig addr1:
mremap(addr2, 4096, 4096, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
In step 3, the vma1 range [addr1, addr1 + 4096] will be remap to new vma2
with range [addr2, addr2 + 8192], and remap uprobe anon page from the vma1
to vma2, then unmap the vma1 range [addr1, addr1 + 4096].
In step 4, the vma2 range [addr2, addr2 + 4096] will be remap back to the
addr range [addr1, addr1 + 4096]. Since the addr range [addr1 + 4096,
addr1 + 8192] still maps the file, it will take vma_merge_new_range to
expand the range, and then do uprobe_mmap in vma_complete. Since the
merged vma pgoff is also zero offset, it will install uprobe anon page to
the merged vma. However, the upcomming move_page_tables step, which use
set_pte_at to remap the vma2 uprobe pte to the merged vma, will overwrite
the newly uprobe pte in the merged vma, and lead that pte to be orphan.
Since the uprobe pte will be remapped to the merged vma, we can remove the
unnecessary uprobe_mmap upon merged vma.
This problem was first found in linux-6.6.y and also exists in the
community syzkaller:
https://lore.kernel.org/all/000000000000ada39605a5e71711@google.com/T/
Link: https://lkml.kernel.org/r/20250529155650.4017699-1-pulehui@huaweicloud.com
Link: https://lkml.kernel.org/r/20250529155650.4017699-2-pulehui@huaweicloud.com
Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints")
Signed-off-by: Pu Lehui <pulehui(a)huawei.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat(a)kernel.org>
Cc: Oleg Nesterov <oleg(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vma.c b/mm/vma.c
index 1c6595f282e5..b2d7c03d8aa4 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -169,6 +169,9 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
vp->file = vma->vm_file;
if (vp->file)
vp->mapping = vma->vm_file->f_mapping;
+
+ if (vmg && vmg->skip_vma_uprobe)
+ vp->skip_vma_uprobe = true;
}
/*
@@ -358,10 +361,13 @@ static void vma_complete(struct vma_prepare *vp, struct vma_iterator *vmi,
if (vp->file) {
i_mmap_unlock_write(vp->mapping);
- uprobe_mmap(vp->vma);
- if (vp->adj_next)
- uprobe_mmap(vp->adj_next);
+ if (!vp->skip_vma_uprobe) {
+ uprobe_mmap(vp->vma);
+
+ if (vp->adj_next)
+ uprobe_mmap(vp->adj_next);
+ }
}
if (vp->remove) {
@@ -1823,6 +1829,14 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
faulted_in_anon_vma = false;
}
+ /*
+ * If the VMA we are copying might contain a uprobe PTE, ensure
+ * that we do not establish one upon merge. Otherwise, when mremap()
+ * moves page tables, it will orphan the newly created PTE.
+ */
+ if (vma->vm_file)
+ vmg.skip_vma_uprobe = true;
+
new_vma = find_vma_prev(mm, addr, &vmg.prev);
if (new_vma && new_vma->vm_start < addr + len)
return NULL; /* should never get here */
diff --git a/mm/vma.h b/mm/vma.h
index 9a8af9be29a8..0db066e7a45d 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -19,6 +19,8 @@ struct vma_prepare {
struct vm_area_struct *insert;
struct vm_area_struct *remove;
struct vm_area_struct *remove2;
+
+ bool skip_vma_uprobe :1;
};
struct unlink_vma_file_batch {
@@ -120,6 +122,11 @@ struct vma_merge_struct {
*/
bool give_up_on_oom :1;
+ /*
+ * If set, skip uprobe_mmap upon merged vma.
+ */
+ bool skip_vma_uprobe :1;
+
/* Internal flags set during merge process: */
/*
The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 2b12d06c37fd3a394376f42f026a7478d826ed63
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062013-apostle-lethargic-d079@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2b12d06c37fd3a394376f42f026a7478d826ed63 Mon Sep 17 00:00:00 2001
From: Pu Lehui <pulehui(a)huawei.com>
Date: Thu, 29 May 2025 15:56:47 +0000
Subject: [PATCH] mm: fix uprobe pte be overwritten when expanding vma
Patch series "Fix uprobe pte be overwritten when expanding vma".
This patch (of 4):
We encountered a BUG alert triggered by Syzkaller as follows:
BUG: Bad rss-counter state mm:00000000b4a60fca type:MM_ANONPAGES val:1
And we can reproduce it with the following steps:
1. register uprobe on file at zero offset
2. mmap the file at zero offset:
addr1 = mmap(NULL, 2 * 4096, PROT_NONE, MAP_PRIVATE, fd, 0);
3. mremap part of vma1 to new vma2:
addr2 = mremap(addr1, 4096, 2 * 4096, MREMAP_MAYMOVE);
4. mremap back to orig addr1:
mremap(addr2, 4096, 4096, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
In step 3, the vma1 range [addr1, addr1 + 4096] will be remap to new vma2
with range [addr2, addr2 + 8192], and remap uprobe anon page from the vma1
to vma2, then unmap the vma1 range [addr1, addr1 + 4096].
In step 4, the vma2 range [addr2, addr2 + 4096] will be remap back to the
addr range [addr1, addr1 + 4096]. Since the addr range [addr1 + 4096,
addr1 + 8192] still maps the file, it will take vma_merge_new_range to
expand the range, and then do uprobe_mmap in vma_complete. Since the
merged vma pgoff is also zero offset, it will install uprobe anon page to
the merged vma. However, the upcomming move_page_tables step, which use
set_pte_at to remap the vma2 uprobe pte to the merged vma, will overwrite
the newly uprobe pte in the merged vma, and lead that pte to be orphan.
Since the uprobe pte will be remapped to the merged vma, we can remove the
unnecessary uprobe_mmap upon merged vma.
This problem was first found in linux-6.6.y and also exists in the
community syzkaller:
https://lore.kernel.org/all/000000000000ada39605a5e71711@google.com/T/
Link: https://lkml.kernel.org/r/20250529155650.4017699-1-pulehui@huaweicloud.com
Link: https://lkml.kernel.org/r/20250529155650.4017699-2-pulehui@huaweicloud.com
Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints")
Signed-off-by: Pu Lehui <pulehui(a)huawei.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat(a)kernel.org>
Cc: Oleg Nesterov <oleg(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vma.c b/mm/vma.c
index 1c6595f282e5..b2d7c03d8aa4 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -169,6 +169,9 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
vp->file = vma->vm_file;
if (vp->file)
vp->mapping = vma->vm_file->f_mapping;
+
+ if (vmg && vmg->skip_vma_uprobe)
+ vp->skip_vma_uprobe = true;
}
/*
@@ -358,10 +361,13 @@ static void vma_complete(struct vma_prepare *vp, struct vma_iterator *vmi,
if (vp->file) {
i_mmap_unlock_write(vp->mapping);
- uprobe_mmap(vp->vma);
- if (vp->adj_next)
- uprobe_mmap(vp->adj_next);
+ if (!vp->skip_vma_uprobe) {
+ uprobe_mmap(vp->vma);
+
+ if (vp->adj_next)
+ uprobe_mmap(vp->adj_next);
+ }
}
if (vp->remove) {
@@ -1823,6 +1829,14 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
faulted_in_anon_vma = false;
}
+ /*
+ * If the VMA we are copying might contain a uprobe PTE, ensure
+ * that we do not establish one upon merge. Otherwise, when mremap()
+ * moves page tables, it will orphan the newly created PTE.
+ */
+ if (vma->vm_file)
+ vmg.skip_vma_uprobe = true;
+
new_vma = find_vma_prev(mm, addr, &vmg.prev);
if (new_vma && new_vma->vm_start < addr + len)
return NULL; /* should never get here */
diff --git a/mm/vma.h b/mm/vma.h
index 9a8af9be29a8..0db066e7a45d 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -19,6 +19,8 @@ struct vma_prepare {
struct vm_area_struct *insert;
struct vm_area_struct *remove;
struct vm_area_struct *remove2;
+
+ bool skip_vma_uprobe :1;
};
struct unlink_vma_file_batch {
@@ -120,6 +122,11 @@ struct vma_merge_struct {
*/
bool give_up_on_oom :1;
+ /*
+ * If set, skip uprobe_mmap upon merged vma.
+ */
+ bool skip_vma_uprobe :1;
+
/* Internal flags set during merge process: */
/*
The patch below does not apply to the 5.15-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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 2b12d06c37fd3a394376f42f026a7478d826ed63
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062012-judge-nemesis-5f60@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2b12d06c37fd3a394376f42f026a7478d826ed63 Mon Sep 17 00:00:00 2001
From: Pu Lehui <pulehui(a)huawei.com>
Date: Thu, 29 May 2025 15:56:47 +0000
Subject: [PATCH] mm: fix uprobe pte be overwritten when expanding vma
Patch series "Fix uprobe pte be overwritten when expanding vma".
This patch (of 4):
We encountered a BUG alert triggered by Syzkaller as follows:
BUG: Bad rss-counter state mm:00000000b4a60fca type:MM_ANONPAGES val:1
And we can reproduce it with the following steps:
1. register uprobe on file at zero offset
2. mmap the file at zero offset:
addr1 = mmap(NULL, 2 * 4096, PROT_NONE, MAP_PRIVATE, fd, 0);
3. mremap part of vma1 to new vma2:
addr2 = mremap(addr1, 4096, 2 * 4096, MREMAP_MAYMOVE);
4. mremap back to orig addr1:
mremap(addr2, 4096, 4096, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
In step 3, the vma1 range [addr1, addr1 + 4096] will be remap to new vma2
with range [addr2, addr2 + 8192], and remap uprobe anon page from the vma1
to vma2, then unmap the vma1 range [addr1, addr1 + 4096].
In step 4, the vma2 range [addr2, addr2 + 4096] will be remap back to the
addr range [addr1, addr1 + 4096]. Since the addr range [addr1 + 4096,
addr1 + 8192] still maps the file, it will take vma_merge_new_range to
expand the range, and then do uprobe_mmap in vma_complete. Since the
merged vma pgoff is also zero offset, it will install uprobe anon page to
the merged vma. However, the upcomming move_page_tables step, which use
set_pte_at to remap the vma2 uprobe pte to the merged vma, will overwrite
the newly uprobe pte in the merged vma, and lead that pte to be orphan.
Since the uprobe pte will be remapped to the merged vma, we can remove the
unnecessary uprobe_mmap upon merged vma.
This problem was first found in linux-6.6.y and also exists in the
community syzkaller:
https://lore.kernel.org/all/000000000000ada39605a5e71711@google.com/T/
Link: https://lkml.kernel.org/r/20250529155650.4017699-1-pulehui@huaweicloud.com
Link: https://lkml.kernel.org/r/20250529155650.4017699-2-pulehui@huaweicloud.com
Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints")
Signed-off-by: Pu Lehui <pulehui(a)huawei.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat(a)kernel.org>
Cc: Oleg Nesterov <oleg(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vma.c b/mm/vma.c
index 1c6595f282e5..b2d7c03d8aa4 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -169,6 +169,9 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
vp->file = vma->vm_file;
if (vp->file)
vp->mapping = vma->vm_file->f_mapping;
+
+ if (vmg && vmg->skip_vma_uprobe)
+ vp->skip_vma_uprobe = true;
}
/*
@@ -358,10 +361,13 @@ static void vma_complete(struct vma_prepare *vp, struct vma_iterator *vmi,
if (vp->file) {
i_mmap_unlock_write(vp->mapping);
- uprobe_mmap(vp->vma);
- if (vp->adj_next)
- uprobe_mmap(vp->adj_next);
+ if (!vp->skip_vma_uprobe) {
+ uprobe_mmap(vp->vma);
+
+ if (vp->adj_next)
+ uprobe_mmap(vp->adj_next);
+ }
}
if (vp->remove) {
@@ -1823,6 +1829,14 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
faulted_in_anon_vma = false;
}
+ /*
+ * If the VMA we are copying might contain a uprobe PTE, ensure
+ * that we do not establish one upon merge. Otherwise, when mremap()
+ * moves page tables, it will orphan the newly created PTE.
+ */
+ if (vma->vm_file)
+ vmg.skip_vma_uprobe = true;
+
new_vma = find_vma_prev(mm, addr, &vmg.prev);
if (new_vma && new_vma->vm_start < addr + len)
return NULL; /* should never get here */
diff --git a/mm/vma.h b/mm/vma.h
index 9a8af9be29a8..0db066e7a45d 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -19,6 +19,8 @@ struct vma_prepare {
struct vm_area_struct *insert;
struct vm_area_struct *remove;
struct vm_area_struct *remove2;
+
+ bool skip_vma_uprobe :1;
};
struct unlink_vma_file_batch {
@@ -120,6 +122,11 @@ struct vma_merge_struct {
*/
bool give_up_on_oom :1;
+ /*
+ * If set, skip uprobe_mmap upon merged vma.
+ */
+ bool skip_vma_uprobe :1;
+
/* Internal flags set during merge process: */
/*
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 2b12d06c37fd3a394376f42f026a7478d826ed63
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062011-earache-whenever-2435@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2b12d06c37fd3a394376f42f026a7478d826ed63 Mon Sep 17 00:00:00 2001
From: Pu Lehui <pulehui(a)huawei.com>
Date: Thu, 29 May 2025 15:56:47 +0000
Subject: [PATCH] mm: fix uprobe pte be overwritten when expanding vma
Patch series "Fix uprobe pte be overwritten when expanding vma".
This patch (of 4):
We encountered a BUG alert triggered by Syzkaller as follows:
BUG: Bad rss-counter state mm:00000000b4a60fca type:MM_ANONPAGES val:1
And we can reproduce it with the following steps:
1. register uprobe on file at zero offset
2. mmap the file at zero offset:
addr1 = mmap(NULL, 2 * 4096, PROT_NONE, MAP_PRIVATE, fd, 0);
3. mremap part of vma1 to new vma2:
addr2 = mremap(addr1, 4096, 2 * 4096, MREMAP_MAYMOVE);
4. mremap back to orig addr1:
mremap(addr2, 4096, 4096, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
In step 3, the vma1 range [addr1, addr1 + 4096] will be remap to new vma2
with range [addr2, addr2 + 8192], and remap uprobe anon page from the vma1
to vma2, then unmap the vma1 range [addr1, addr1 + 4096].
In step 4, the vma2 range [addr2, addr2 + 4096] will be remap back to the
addr range [addr1, addr1 + 4096]. Since the addr range [addr1 + 4096,
addr1 + 8192] still maps the file, it will take vma_merge_new_range to
expand the range, and then do uprobe_mmap in vma_complete. Since the
merged vma pgoff is also zero offset, it will install uprobe anon page to
the merged vma. However, the upcomming move_page_tables step, which use
set_pte_at to remap the vma2 uprobe pte to the merged vma, will overwrite
the newly uprobe pte in the merged vma, and lead that pte to be orphan.
Since the uprobe pte will be remapped to the merged vma, we can remove the
unnecessary uprobe_mmap upon merged vma.
This problem was first found in linux-6.6.y and also exists in the
community syzkaller:
https://lore.kernel.org/all/000000000000ada39605a5e71711@google.com/T/
Link: https://lkml.kernel.org/r/20250529155650.4017699-1-pulehui@huaweicloud.com
Link: https://lkml.kernel.org/r/20250529155650.4017699-2-pulehui@huaweicloud.com
Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints")
Signed-off-by: Pu Lehui <pulehui(a)huawei.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat(a)kernel.org>
Cc: Oleg Nesterov <oleg(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vma.c b/mm/vma.c
index 1c6595f282e5..b2d7c03d8aa4 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -169,6 +169,9 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
vp->file = vma->vm_file;
if (vp->file)
vp->mapping = vma->vm_file->f_mapping;
+
+ if (vmg && vmg->skip_vma_uprobe)
+ vp->skip_vma_uprobe = true;
}
/*
@@ -358,10 +361,13 @@ static void vma_complete(struct vma_prepare *vp, struct vma_iterator *vmi,
if (vp->file) {
i_mmap_unlock_write(vp->mapping);
- uprobe_mmap(vp->vma);
- if (vp->adj_next)
- uprobe_mmap(vp->adj_next);
+ if (!vp->skip_vma_uprobe) {
+ uprobe_mmap(vp->vma);
+
+ if (vp->adj_next)
+ uprobe_mmap(vp->adj_next);
+ }
}
if (vp->remove) {
@@ -1823,6 +1829,14 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
faulted_in_anon_vma = false;
}
+ /*
+ * If the VMA we are copying might contain a uprobe PTE, ensure
+ * that we do not establish one upon merge. Otherwise, when mremap()
+ * moves page tables, it will orphan the newly created PTE.
+ */
+ if (vma->vm_file)
+ vmg.skip_vma_uprobe = true;
+
new_vma = find_vma_prev(mm, addr, &vmg.prev);
if (new_vma && new_vma->vm_start < addr + len)
return NULL; /* should never get here */
diff --git a/mm/vma.h b/mm/vma.h
index 9a8af9be29a8..0db066e7a45d 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -19,6 +19,8 @@ struct vma_prepare {
struct vm_area_struct *insert;
struct vm_area_struct *remove;
struct vm_area_struct *remove2;
+
+ bool skip_vma_uprobe :1;
};
struct unlink_vma_file_batch {
@@ -120,6 +122,11 @@ struct vma_merge_struct {
*/
bool give_up_on_oom :1;
+ /*
+ * If set, skip uprobe_mmap upon merged vma.
+ */
+ bool skip_vma_uprobe :1;
+
/* Internal flags set during merge process: */
/*
The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 2b12d06c37fd3a394376f42f026a7478d826ed63
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062009-customs-outskirts-5826@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2b12d06c37fd3a394376f42f026a7478d826ed63 Mon Sep 17 00:00:00 2001
From: Pu Lehui <pulehui(a)huawei.com>
Date: Thu, 29 May 2025 15:56:47 +0000
Subject: [PATCH] mm: fix uprobe pte be overwritten when expanding vma
Patch series "Fix uprobe pte be overwritten when expanding vma".
This patch (of 4):
We encountered a BUG alert triggered by Syzkaller as follows:
BUG: Bad rss-counter state mm:00000000b4a60fca type:MM_ANONPAGES val:1
And we can reproduce it with the following steps:
1. register uprobe on file at zero offset
2. mmap the file at zero offset:
addr1 = mmap(NULL, 2 * 4096, PROT_NONE, MAP_PRIVATE, fd, 0);
3. mremap part of vma1 to new vma2:
addr2 = mremap(addr1, 4096, 2 * 4096, MREMAP_MAYMOVE);
4. mremap back to orig addr1:
mremap(addr2, 4096, 4096, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
In step 3, the vma1 range [addr1, addr1 + 4096] will be remap to new vma2
with range [addr2, addr2 + 8192], and remap uprobe anon page from the vma1
to vma2, then unmap the vma1 range [addr1, addr1 + 4096].
In step 4, the vma2 range [addr2, addr2 + 4096] will be remap back to the
addr range [addr1, addr1 + 4096]. Since the addr range [addr1 + 4096,
addr1 + 8192] still maps the file, it will take vma_merge_new_range to
expand the range, and then do uprobe_mmap in vma_complete. Since the
merged vma pgoff is also zero offset, it will install uprobe anon page to
the merged vma. However, the upcomming move_page_tables step, which use
set_pte_at to remap the vma2 uprobe pte to the merged vma, will overwrite
the newly uprobe pte in the merged vma, and lead that pte to be orphan.
Since the uprobe pte will be remapped to the merged vma, we can remove the
unnecessary uprobe_mmap upon merged vma.
This problem was first found in linux-6.6.y and also exists in the
community syzkaller:
https://lore.kernel.org/all/000000000000ada39605a5e71711@google.com/T/
Link: https://lkml.kernel.org/r/20250529155650.4017699-1-pulehui@huaweicloud.com
Link: https://lkml.kernel.org/r/20250529155650.4017699-2-pulehui@huaweicloud.com
Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints")
Signed-off-by: Pu Lehui <pulehui(a)huawei.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat(a)kernel.org>
Cc: Oleg Nesterov <oleg(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vma.c b/mm/vma.c
index 1c6595f282e5..b2d7c03d8aa4 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -169,6 +169,9 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
vp->file = vma->vm_file;
if (vp->file)
vp->mapping = vma->vm_file->f_mapping;
+
+ if (vmg && vmg->skip_vma_uprobe)
+ vp->skip_vma_uprobe = true;
}
/*
@@ -358,10 +361,13 @@ static void vma_complete(struct vma_prepare *vp, struct vma_iterator *vmi,
if (vp->file) {
i_mmap_unlock_write(vp->mapping);
- uprobe_mmap(vp->vma);
- if (vp->adj_next)
- uprobe_mmap(vp->adj_next);
+ if (!vp->skip_vma_uprobe) {
+ uprobe_mmap(vp->vma);
+
+ if (vp->adj_next)
+ uprobe_mmap(vp->adj_next);
+ }
}
if (vp->remove) {
@@ -1823,6 +1829,14 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
faulted_in_anon_vma = false;
}
+ /*
+ * If the VMA we are copying might contain a uprobe PTE, ensure
+ * that we do not establish one upon merge. Otherwise, when mremap()
+ * moves page tables, it will orphan the newly created PTE.
+ */
+ if (vma->vm_file)
+ vmg.skip_vma_uprobe = true;
+
new_vma = find_vma_prev(mm, addr, &vmg.prev);
if (new_vma && new_vma->vm_start < addr + len)
return NULL; /* should never get here */
diff --git a/mm/vma.h b/mm/vma.h
index 9a8af9be29a8..0db066e7a45d 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -19,6 +19,8 @@ struct vma_prepare {
struct vm_area_struct *insert;
struct vm_area_struct *remove;
struct vm_area_struct *remove2;
+
+ bool skip_vma_uprobe :1;
};
struct unlink_vma_file_batch {
@@ -120,6 +122,11 @@ struct vma_merge_struct {
*/
bool give_up_on_oom :1;
+ /*
+ * If set, skip uprobe_mmap upon merged vma.
+ */
+ bool skip_vma_uprobe :1;
+
/* Internal flags set during merge process: */
/*
The patch below does not apply to the 6.12-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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 2b12d06c37fd3a394376f42f026a7478d826ed63
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062008-scarcity-jaundice-0b6e@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2b12d06c37fd3a394376f42f026a7478d826ed63 Mon Sep 17 00:00:00 2001
From: Pu Lehui <pulehui(a)huawei.com>
Date: Thu, 29 May 2025 15:56:47 +0000
Subject: [PATCH] mm: fix uprobe pte be overwritten when expanding vma
Patch series "Fix uprobe pte be overwritten when expanding vma".
This patch (of 4):
We encountered a BUG alert triggered by Syzkaller as follows:
BUG: Bad rss-counter state mm:00000000b4a60fca type:MM_ANONPAGES val:1
And we can reproduce it with the following steps:
1. register uprobe on file at zero offset
2. mmap the file at zero offset:
addr1 = mmap(NULL, 2 * 4096, PROT_NONE, MAP_PRIVATE, fd, 0);
3. mremap part of vma1 to new vma2:
addr2 = mremap(addr1, 4096, 2 * 4096, MREMAP_MAYMOVE);
4. mremap back to orig addr1:
mremap(addr2, 4096, 4096, MREMAP_MAYMOVE | MREMAP_FIXED, addr1);
In step 3, the vma1 range [addr1, addr1 + 4096] will be remap to new vma2
with range [addr2, addr2 + 8192], and remap uprobe anon page from the vma1
to vma2, then unmap the vma1 range [addr1, addr1 + 4096].
In step 4, the vma2 range [addr2, addr2 + 4096] will be remap back to the
addr range [addr1, addr1 + 4096]. Since the addr range [addr1 + 4096,
addr1 + 8192] still maps the file, it will take vma_merge_new_range to
expand the range, and then do uprobe_mmap in vma_complete. Since the
merged vma pgoff is also zero offset, it will install uprobe anon page to
the merged vma. However, the upcomming move_page_tables step, which use
set_pte_at to remap the vma2 uprobe pte to the merged vma, will overwrite
the newly uprobe pte in the merged vma, and lead that pte to be orphan.
Since the uprobe pte will be remapped to the merged vma, we can remove the
unnecessary uprobe_mmap upon merged vma.
This problem was first found in linux-6.6.y and also exists in the
community syzkaller:
https://lore.kernel.org/all/000000000000ada39605a5e71711@google.com/T/
Link: https://lkml.kernel.org/r/20250529155650.4017699-1-pulehui@huaweicloud.com
Link: https://lkml.kernel.org/r/20250529155650.4017699-2-pulehui@huaweicloud.com
Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints")
Signed-off-by: Pu Lehui <pulehui(a)huawei.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat(a)kernel.org>
Cc: Oleg Nesterov <oleg(a)redhat.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vma.c b/mm/vma.c
index 1c6595f282e5..b2d7c03d8aa4 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -169,6 +169,9 @@ static void init_multi_vma_prep(struct vma_prepare *vp,
vp->file = vma->vm_file;
if (vp->file)
vp->mapping = vma->vm_file->f_mapping;
+
+ if (vmg && vmg->skip_vma_uprobe)
+ vp->skip_vma_uprobe = true;
}
/*
@@ -358,10 +361,13 @@ static void vma_complete(struct vma_prepare *vp, struct vma_iterator *vmi,
if (vp->file) {
i_mmap_unlock_write(vp->mapping);
- uprobe_mmap(vp->vma);
- if (vp->adj_next)
- uprobe_mmap(vp->adj_next);
+ if (!vp->skip_vma_uprobe) {
+ uprobe_mmap(vp->vma);
+
+ if (vp->adj_next)
+ uprobe_mmap(vp->adj_next);
+ }
}
if (vp->remove) {
@@ -1823,6 +1829,14 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
faulted_in_anon_vma = false;
}
+ /*
+ * If the VMA we are copying might contain a uprobe PTE, ensure
+ * that we do not establish one upon merge. Otherwise, when mremap()
+ * moves page tables, it will orphan the newly created PTE.
+ */
+ if (vma->vm_file)
+ vmg.skip_vma_uprobe = true;
+
new_vma = find_vma_prev(mm, addr, &vmg.prev);
if (new_vma && new_vma->vm_start < addr + len)
return NULL; /* should never get here */
diff --git a/mm/vma.h b/mm/vma.h
index 9a8af9be29a8..0db066e7a45d 100644
--- a/mm/vma.h
+++ b/mm/vma.h
@@ -19,6 +19,8 @@ struct vma_prepare {
struct vm_area_struct *insert;
struct vm_area_struct *remove;
struct vm_area_struct *remove2;
+
+ bool skip_vma_uprobe :1;
};
struct unlink_vma_file_batch {
@@ -120,6 +122,11 @@ struct vma_merge_struct {
*/
bool give_up_on_oom :1;
+ /*
+ * If set, skip uprobe_mmap upon merged vma.
+ */
+ bool skip_vma_uprobe :1;
+
/* Internal flags set during merge process: */
/*
The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 03bcbbb3995ba5df43af9aba45334e35f2dfe27b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062045-bungee-spooky-6ffe@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 03bcbbb3995ba5df43af9aba45334e35f2dfe27b Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann(a)suse.de>
Date: Tue, 20 May 2025 09:14:00 +0200
Subject: [PATCH] dummycon: Trigger redraw when switching consoles with
deferred takeover
Signal vt subsystem to redraw console when switching to dummycon
with deferred takeover enabled. Makes the console switch to fbcon
and displays the available output.
With deferred takeover enabled, dummycon acts as the placeholder
until the first output to the console happens. At that point, fbcon
takes over. If the output happens while dummycon is not active, it
cannot inform fbcon. This is the case if the vt subsystem runs in
graphics mode.
A typical graphical boot starts plymouth, a display manager and a
compositor; all while leaving out dummycon. Switching to a text-mode
console leaves the console with dummycon even if a getty terminal
has been started.
Returning true from dummycon's con_switch helper signals the vt
subsystem to redraw the screen. If there's output available dummycon's
con_putc{s} helpers trigger deferred takeover of fbcon, which sets a
display mode and displays the output. If no output is available,
dummycon remains active.
v2:
- make the comment slightly more verbose (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reported-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Closes: https://bugzilla.suse.com/show_bug.cgi?id=1242191
Tested-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Acked-by: Javier Martinez Canillas <javierm(a)redhat.com>
Fixes: 83d83bebf401 ("console/fbcon: Add support for deferred console takeover")
Cc: Hans de Goede <hdegoede(a)redhat.com>
Cc: linux-fbdev(a)vger.kernel.org
Cc: dri-devel(a)lists.freedesktop.org
Cc: <stable(a)vger.kernel.org> # v4.19+
Link: https://lore.kernel.org/r/20250520071418.8462-1-tzimmermann@suse.de
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 139049368fdc..7d02470f19b9 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -85,6 +85,15 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
/* Redraw, so that we get putc(s) for output done while blanked */
return true;
}
+
+static bool dummycon_switch(struct vc_data *vc)
+{
+ /*
+ * Redraw, so that we get putc(s) for output done while switched
+ * away. Informs deferred consoles to take over the display.
+ */
+ return true;
+}
#else
static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
unsigned int x) { }
@@ -95,6 +104,10 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
{
return false;
}
+static bool dummycon_switch(struct vc_data *vc)
+{
+ return false;
+}
#endif
static const char *dummycon_startup(void)
@@ -124,11 +137,6 @@ static bool dummycon_scroll(struct vc_data *vc, unsigned int top,
return false;
}
-static bool dummycon_switch(struct vc_data *vc)
-{
- return false;
-}
-
/*
* The console `switch' structure for the dummy console
*
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 03bcbbb3995ba5df43af9aba45334e35f2dfe27b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062042-wound-marathon-63cd@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 03bcbbb3995ba5df43af9aba45334e35f2dfe27b Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann(a)suse.de>
Date: Tue, 20 May 2025 09:14:00 +0200
Subject: [PATCH] dummycon: Trigger redraw when switching consoles with
deferred takeover
Signal vt subsystem to redraw console when switching to dummycon
with deferred takeover enabled. Makes the console switch to fbcon
and displays the available output.
With deferred takeover enabled, dummycon acts as the placeholder
until the first output to the console happens. At that point, fbcon
takes over. If the output happens while dummycon is not active, it
cannot inform fbcon. This is the case if the vt subsystem runs in
graphics mode.
A typical graphical boot starts plymouth, a display manager and a
compositor; all while leaving out dummycon. Switching to a text-mode
console leaves the console with dummycon even if a getty terminal
has been started.
Returning true from dummycon's con_switch helper signals the vt
subsystem to redraw the screen. If there's output available dummycon's
con_putc{s} helpers trigger deferred takeover of fbcon, which sets a
display mode and displays the output. If no output is available,
dummycon remains active.
v2:
- make the comment slightly more verbose (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reported-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Closes: https://bugzilla.suse.com/show_bug.cgi?id=1242191
Tested-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Acked-by: Javier Martinez Canillas <javierm(a)redhat.com>
Fixes: 83d83bebf401 ("console/fbcon: Add support for deferred console takeover")
Cc: Hans de Goede <hdegoede(a)redhat.com>
Cc: linux-fbdev(a)vger.kernel.org
Cc: dri-devel(a)lists.freedesktop.org
Cc: <stable(a)vger.kernel.org> # v4.19+
Link: https://lore.kernel.org/r/20250520071418.8462-1-tzimmermann@suse.de
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 139049368fdc..7d02470f19b9 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -85,6 +85,15 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
/* Redraw, so that we get putc(s) for output done while blanked */
return true;
}
+
+static bool dummycon_switch(struct vc_data *vc)
+{
+ /*
+ * Redraw, so that we get putc(s) for output done while switched
+ * away. Informs deferred consoles to take over the display.
+ */
+ return true;
+}
#else
static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
unsigned int x) { }
@@ -95,6 +104,10 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
{
return false;
}
+static bool dummycon_switch(struct vc_data *vc)
+{
+ return false;
+}
#endif
static const char *dummycon_startup(void)
@@ -124,11 +137,6 @@ static bool dummycon_scroll(struct vc_data *vc, unsigned int top,
return false;
}
-static bool dummycon_switch(struct vc_data *vc)
-{
- return false;
-}
-
/*
* The console `switch' structure for the dummy console
*
The patch below does not apply to the 5.15-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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 03bcbbb3995ba5df43af9aba45334e35f2dfe27b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062041-wrecking-disgrace-7467@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 03bcbbb3995ba5df43af9aba45334e35f2dfe27b Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann(a)suse.de>
Date: Tue, 20 May 2025 09:14:00 +0200
Subject: [PATCH] dummycon: Trigger redraw when switching consoles with
deferred takeover
Signal vt subsystem to redraw console when switching to dummycon
with deferred takeover enabled. Makes the console switch to fbcon
and displays the available output.
With deferred takeover enabled, dummycon acts as the placeholder
until the first output to the console happens. At that point, fbcon
takes over. If the output happens while dummycon is not active, it
cannot inform fbcon. This is the case if the vt subsystem runs in
graphics mode.
A typical graphical boot starts plymouth, a display manager and a
compositor; all while leaving out dummycon. Switching to a text-mode
console leaves the console with dummycon even if a getty terminal
has been started.
Returning true from dummycon's con_switch helper signals the vt
subsystem to redraw the screen. If there's output available dummycon's
con_putc{s} helpers trigger deferred takeover of fbcon, which sets a
display mode and displays the output. If no output is available,
dummycon remains active.
v2:
- make the comment slightly more verbose (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reported-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Closes: https://bugzilla.suse.com/show_bug.cgi?id=1242191
Tested-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Acked-by: Javier Martinez Canillas <javierm(a)redhat.com>
Fixes: 83d83bebf401 ("console/fbcon: Add support for deferred console takeover")
Cc: Hans de Goede <hdegoede(a)redhat.com>
Cc: linux-fbdev(a)vger.kernel.org
Cc: dri-devel(a)lists.freedesktop.org
Cc: <stable(a)vger.kernel.org> # v4.19+
Link: https://lore.kernel.org/r/20250520071418.8462-1-tzimmermann@suse.de
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 139049368fdc..7d02470f19b9 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -85,6 +85,15 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
/* Redraw, so that we get putc(s) for output done while blanked */
return true;
}
+
+static bool dummycon_switch(struct vc_data *vc)
+{
+ /*
+ * Redraw, so that we get putc(s) for output done while switched
+ * away. Informs deferred consoles to take over the display.
+ */
+ return true;
+}
#else
static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
unsigned int x) { }
@@ -95,6 +104,10 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
{
return false;
}
+static bool dummycon_switch(struct vc_data *vc)
+{
+ return false;
+}
#endif
static const char *dummycon_startup(void)
@@ -124,11 +137,6 @@ static bool dummycon_scroll(struct vc_data *vc, unsigned int top,
return false;
}
-static bool dummycon_switch(struct vc_data *vc)
-{
- return false;
-}
-
/*
* The console `switch' structure for the dummy console
*
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 03bcbbb3995ba5df43af9aba45334e35f2dfe27b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062040-scarring-repeal-109f@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 03bcbbb3995ba5df43af9aba45334e35f2dfe27b Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann(a)suse.de>
Date: Tue, 20 May 2025 09:14:00 +0200
Subject: [PATCH] dummycon: Trigger redraw when switching consoles with
deferred takeover
Signal vt subsystem to redraw console when switching to dummycon
with deferred takeover enabled. Makes the console switch to fbcon
and displays the available output.
With deferred takeover enabled, dummycon acts as the placeholder
until the first output to the console happens. At that point, fbcon
takes over. If the output happens while dummycon is not active, it
cannot inform fbcon. This is the case if the vt subsystem runs in
graphics mode.
A typical graphical boot starts plymouth, a display manager and a
compositor; all while leaving out dummycon. Switching to a text-mode
console leaves the console with dummycon even if a getty terminal
has been started.
Returning true from dummycon's con_switch helper signals the vt
subsystem to redraw the screen. If there's output available dummycon's
con_putc{s} helpers trigger deferred takeover of fbcon, which sets a
display mode and displays the output. If no output is available,
dummycon remains active.
v2:
- make the comment slightly more verbose (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reported-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Closes: https://bugzilla.suse.com/show_bug.cgi?id=1242191
Tested-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Acked-by: Javier Martinez Canillas <javierm(a)redhat.com>
Fixes: 83d83bebf401 ("console/fbcon: Add support for deferred console takeover")
Cc: Hans de Goede <hdegoede(a)redhat.com>
Cc: linux-fbdev(a)vger.kernel.org
Cc: dri-devel(a)lists.freedesktop.org
Cc: <stable(a)vger.kernel.org> # v4.19+
Link: https://lore.kernel.org/r/20250520071418.8462-1-tzimmermann@suse.de
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 139049368fdc..7d02470f19b9 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -85,6 +85,15 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
/* Redraw, so that we get putc(s) for output done while blanked */
return true;
}
+
+static bool dummycon_switch(struct vc_data *vc)
+{
+ /*
+ * Redraw, so that we get putc(s) for output done while switched
+ * away. Informs deferred consoles to take over the display.
+ */
+ return true;
+}
#else
static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
unsigned int x) { }
@@ -95,6 +104,10 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
{
return false;
}
+static bool dummycon_switch(struct vc_data *vc)
+{
+ return false;
+}
#endif
static const char *dummycon_startup(void)
@@ -124,11 +137,6 @@ static bool dummycon_scroll(struct vc_data *vc, unsigned int top,
return false;
}
-static bool dummycon_switch(struct vc_data *vc)
-{
- return false;
-}
-
/*
* The console `switch' structure for the dummy console
*
The patch below does not apply to the 6.6-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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 03bcbbb3995ba5df43af9aba45334e35f2dfe27b
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062039-serving-unbutton-6eaf@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 03bcbbb3995ba5df43af9aba45334e35f2dfe27b Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann(a)suse.de>
Date: Tue, 20 May 2025 09:14:00 +0200
Subject: [PATCH] dummycon: Trigger redraw when switching consoles with
deferred takeover
Signal vt subsystem to redraw console when switching to dummycon
with deferred takeover enabled. Makes the console switch to fbcon
and displays the available output.
With deferred takeover enabled, dummycon acts as the placeholder
until the first output to the console happens. At that point, fbcon
takes over. If the output happens while dummycon is not active, it
cannot inform fbcon. This is the case if the vt subsystem runs in
graphics mode.
A typical graphical boot starts plymouth, a display manager and a
compositor; all while leaving out dummycon. Switching to a text-mode
console leaves the console with dummycon even if a getty terminal
has been started.
Returning true from dummycon's con_switch helper signals the vt
subsystem to redraw the screen. If there's output available dummycon's
con_putc{s} helpers trigger deferred takeover of fbcon, which sets a
display mode and displays the output. If no output is available,
dummycon remains active.
v2:
- make the comment slightly more verbose (Javier)
Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de>
Reported-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Closes: https://bugzilla.suse.com/show_bug.cgi?id=1242191
Tested-by: Andrei Borzenkov <arvidjaar(a)gmail.com>
Acked-by: Javier Martinez Canillas <javierm(a)redhat.com>
Fixes: 83d83bebf401 ("console/fbcon: Add support for deferred console takeover")
Cc: Hans de Goede <hdegoede(a)redhat.com>
Cc: linux-fbdev(a)vger.kernel.org
Cc: dri-devel(a)lists.freedesktop.org
Cc: <stable(a)vger.kernel.org> # v4.19+
Link: https://lore.kernel.org/r/20250520071418.8462-1-tzimmermann@suse.de
diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 139049368fdc..7d02470f19b9 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -85,6 +85,15 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
/* Redraw, so that we get putc(s) for output done while blanked */
return true;
}
+
+static bool dummycon_switch(struct vc_data *vc)
+{
+ /*
+ * Redraw, so that we get putc(s) for output done while switched
+ * away. Informs deferred consoles to take over the display.
+ */
+ return true;
+}
#else
static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
unsigned int x) { }
@@ -95,6 +104,10 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
{
return false;
}
+static bool dummycon_switch(struct vc_data *vc)
+{
+ return false;
+}
#endif
static const char *dummycon_startup(void)
@@ -124,11 +137,6 @@ static bool dummycon_scroll(struct vc_data *vc, unsigned int top,
return false;
}
-static bool dummycon_switch(struct vc_data *vc)
-{
- return false;
-}
-
/*
* The console `switch' structure for the dummy console
*
Link up the CPU regulators for DVFS, enable WiFi and Bluetooth.
Different board versions use different incompatible WiFi/Bluetooth modules
so split the version-specific bits out into an overlay. Basic WiFi
functionality works even without an overlay, but OOB interrupts and
all Bluetooth stuff requires one.
My board is v1.2, so the overlay is only provided for it.
Signed-off-by: Alexey Charkov <alchark(a)gmail.com>
---
Changes in v2:
- Expand the commit message for the patch linking CPU regulators and add
tags for stable (thanks Nicolas)
- Fix the ordering of cpu_b* nodes vs. combphy0_ps (thanks Diederik)
- Drop the USB patch, as Nicolas has already posted a more comprehensive
series including also the Type-C stuff (thanks Nicolas)
- Pick up Nicolas' tags
- Split out board version specific WiFi/Bluetooth stuff into an overlay
- Link to v1: https://lore.kernel.org/r/20250603-sige5-updates-v1-0-717e8ce4ab77@gmail.com
---
Alexey Charkov (4):
arm64: dts: rockchip: list all CPU supplies on ArmSoM Sige5
arm64: dts: rockchip: add SDIO controller on RK3576
arm64: dts: rockchip: add version-independent WiFi/BT nodes on Sige5
arm64: dts: rockchip: add overlay for the WiFi/BT module on Sige5 v1.2
arch/arm64/boot/dts/rockchip/Makefile | 5 ++
.../rockchip/rk3576-armsom-sige5-v1.2-wifibt.dtso | 49 +++++++++++++
.../boot/dts/rockchip/rk3576-armsom-sige5.dts | 85 ++++++++++++++++++++++
arch/arm64/boot/dts/rockchip/rk3576.dtsi | 16 ++++
4 files changed, 155 insertions(+)
---
base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494
change-id: 20250602-sige5-updates-a162b501a1b1
Best regards,
--
Alexey Charkov <alchark(a)gmail.com>