From: Fushuai Wang <wangfushuai(a)baidu.com>
Problem
-------
With CONFIG_X86_DEBUG_FPU enabled, reading /proc/[kthread]/arch_status
causes a kernel NULL pointer dereference.
Kernel threads aren't expected to access the FPU state directly. Kernel
usage of FPU registers is contained within kernel_fpu_begin()/_end()
sections.
However, to report AVX-512 usage, the avx512_timestamp variable within
struct fpu needs to be accessed, which triggers a warning in
x86_task_fpu().
For Kthreads:
proc_pid_arch_status()
avx512_status()
x86_task_fpu() => Warning and returns NULL
x86_task_fpu()->avx512_timestamp => NULL dereference
The warning is a false alarm in this case, since the access isn't
intended for modifying the FPU state. All kernel threads (except the
init_task) have a "struct fpu" with an accessible avx512_timestamp
variable. The init_task (PID 0) never follows this path since it is not
exposed in /proc.
Solution
--------
One option is to get rid of the warning in x86_task_fpu() for kernel
threads. However, that warning was recently added and might be useful to
catch any potential misuse of the FPU state in kernel threads.
Another option is to avoid the access altogether. The kernel does not
track AVX-512 usage for kernel threads.
save_fpregs_to_fpstate()->update_avx_timestamp() is never invoked for
kernel threads, so avx512_timestamp is always guaranteed to be 0.
Also, the legacy behavior of reporting "AVX512_elapsed_ms: -1", which
signifies "no AVX-512 usage", is misleading. The kernel usage just isn't
tracked.
Update the ABI for kernel threads and do not report AVX-512 usage for
them. Not having a value in the file avoids the NULL dereference as well
as the misleading report.
Suggested-by: Dave Hansen <dave.hansen(a)intel.com>
Fixes: 22aafe3bcb67 ("x86/fpu: Remove init_task FPU state dependencies, add debugging warning for PF_KTHREAD tasks")
Cc: stable(a)vger.kernel.org
Signed-off-by: Fushuai Wang <wangfushuai(a)baidu.com>
Co-developed-by: Sohil Mehta <sohil.mehta(a)intel.com>
Signed-off-by: Sohil Mehta <sohil.mehta(a)intel.com>
---
v3:
- Do not report anything for kernel threads. (DaveH)
- Make the commit message more precise.
v2: https://lore.kernel.org/lkml/20250721215302.3562784-1-sohil.mehta@intel.com/
- Avoid making the fix dependent on CONFIG_X86_DEBUG_FPU.
- Include PF_USER_WORKER in the kernel thread check.
- Update commit message for clarity.
---
arch/x86/kernel/fpu/xstate.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 9aa9ac8399ae..b90b2eec8fb8 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1855,19 +1855,20 @@ long fpu_xstate_prctl(int option, unsigned long arg2)
#ifdef CONFIG_PROC_PID_ARCH_STATUS
/*
* Report the amount of time elapsed in millisecond since last AVX512
- * use in the task.
+ * use in the task. Report -1 if no AVX-512 usage.
*/
static void avx512_status(struct seq_file *m, struct task_struct *task)
{
- unsigned long timestamp = READ_ONCE(x86_task_fpu(task)->avx512_timestamp);
- long delta;
+ unsigned long timestamp;
+ long delta = -1;
- if (!timestamp) {
- /*
- * Report -1 if no AVX512 usage
- */
- delta = -1;
- } else {
+ /* AVX-512 usage is not tracked for kernel threads. */
+ if (task->flags & (PF_KTHREAD | PF_USER_WORKER))
+ return;
+
+ timestamp = READ_ONCE(x86_task_fpu(task)->avx512_timestamp);
+
+ if (timestamp) {
delta = (long)(jiffies - timestamp);
/*
* Cap to LONG_MAX if time difference > LONG_MAX
--
2.43.0
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 bec15191d52300defa282e3fd83820f69e447116
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025070814-evict-shelf-8b8d@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bec15191d52300defa282e3fd83820f69e447116 Mon Sep 17 00:00:00 2001
From: RD Babiera <rdbabiera(a)google.com>
Date: Wed, 18 Jun 2025 23:06:04 +0000
Subject: [PATCH] usb: typec: tcpm: apply vbus before data bringup in
tcpm_src_attach
This patch fixes Type-C compliance test TD 4.7.6 - Try.SNK DRP Connect
SNKAS.
tVbusON has a limit of 275ms when entering SRC_ATTACHED. Compliance
testers can interpret the TryWait.Src to Attached.Src transition after
Try.Snk as being in Attached.Src the entire time, so ~170ms is lost
to the debounce timer.
Setting the data role can be a costly operation in host mode, and when
completed after 100ms can cause Type-C compliance test check TD 4.7.5.V.4
to fail.
Turn VBUS on before tcpm_set_roles to meet timing requirement.
Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable <stable(a)kernel.org>
Signed-off-by: RD Babiera <rdbabiera(a)google.com>
Reviewed-by: Badhri Jagan Sridharan <badhri(a)google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus(a)linux.intel.com>
Link: https://lore.kernel.org/r/20250618230606.3272497-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 1a1f9e1f8e4e..1f6fdfaa34bf 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4410,17 +4410,6 @@ static int tcpm_src_attach(struct tcpm_port *port)
tcpm_enable_auto_vbus_discharge(port, true);
- ret = tcpm_set_roles(port, true, TYPEC_STATE_USB,
- TYPEC_SOURCE, tcpm_data_role_for_source(port));
- if (ret < 0)
- return ret;
-
- if (port->pd_supported) {
- ret = port->tcpc->set_pd_rx(port->tcpc, true);
- if (ret < 0)
- goto out_disable_mux;
- }
-
/*
* USB Type-C specification, version 1.2,
* chapter 4.5.2.2.8.1 (Attached.SRC Requirements)
@@ -4430,13 +4419,24 @@ static int tcpm_src_attach(struct tcpm_port *port)
(polarity == TYPEC_POLARITY_CC2 && port->cc1 == TYPEC_CC_RA)) {
ret = tcpm_set_vconn(port, true);
if (ret < 0)
- goto out_disable_pd;
+ return ret;
}
ret = tcpm_set_vbus(port, true);
if (ret < 0)
goto out_disable_vconn;
+ ret = tcpm_set_roles(port, true, TYPEC_STATE_USB, TYPEC_SOURCE,
+ tcpm_data_role_for_source(port));
+ if (ret < 0)
+ goto out_disable_vbus;
+
+ if (port->pd_supported) {
+ ret = port->tcpc->set_pd_rx(port->tcpc, true);
+ if (ret < 0)
+ goto out_disable_mux;
+ }
+
port->pd_capable = false;
port->partner = NULL;
@@ -4447,14 +4447,14 @@ static int tcpm_src_attach(struct tcpm_port *port)
return 0;
-out_disable_vconn:
- tcpm_set_vconn(port, false);
-out_disable_pd:
- if (port->pd_supported)
- port->tcpc->set_pd_rx(port->tcpc, false);
out_disable_mux:
tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
TYPEC_ORIENTATION_NONE);
+out_disable_vbus:
+ tcpm_set_vbus(port, false);
+out_disable_vconn:
+ tcpm_set_vconn(port, false);
+
return ret;
}
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 bec15191d52300defa282e3fd83820f69e447116
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025070815-spongy-caravan-a8f7@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bec15191d52300defa282e3fd83820f69e447116 Mon Sep 17 00:00:00 2001
From: RD Babiera <rdbabiera(a)google.com>
Date: Wed, 18 Jun 2025 23:06:04 +0000
Subject: [PATCH] usb: typec: tcpm: apply vbus before data bringup in
tcpm_src_attach
This patch fixes Type-C compliance test TD 4.7.6 - Try.SNK DRP Connect
SNKAS.
tVbusON has a limit of 275ms when entering SRC_ATTACHED. Compliance
testers can interpret the TryWait.Src to Attached.Src transition after
Try.Snk as being in Attached.Src the entire time, so ~170ms is lost
to the debounce timer.
Setting the data role can be a costly operation in host mode, and when
completed after 100ms can cause Type-C compliance test check TD 4.7.5.V.4
to fail.
Turn VBUS on before tcpm_set_roles to meet timing requirement.
Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable <stable(a)kernel.org>
Signed-off-by: RD Babiera <rdbabiera(a)google.com>
Reviewed-by: Badhri Jagan Sridharan <badhri(a)google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus(a)linux.intel.com>
Link: https://lore.kernel.org/r/20250618230606.3272497-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 1a1f9e1f8e4e..1f6fdfaa34bf 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4410,17 +4410,6 @@ static int tcpm_src_attach(struct tcpm_port *port)
tcpm_enable_auto_vbus_discharge(port, true);
- ret = tcpm_set_roles(port, true, TYPEC_STATE_USB,
- TYPEC_SOURCE, tcpm_data_role_for_source(port));
- if (ret < 0)
- return ret;
-
- if (port->pd_supported) {
- ret = port->tcpc->set_pd_rx(port->tcpc, true);
- if (ret < 0)
- goto out_disable_mux;
- }
-
/*
* USB Type-C specification, version 1.2,
* chapter 4.5.2.2.8.1 (Attached.SRC Requirements)
@@ -4430,13 +4419,24 @@ static int tcpm_src_attach(struct tcpm_port *port)
(polarity == TYPEC_POLARITY_CC2 && port->cc1 == TYPEC_CC_RA)) {
ret = tcpm_set_vconn(port, true);
if (ret < 0)
- goto out_disable_pd;
+ return ret;
}
ret = tcpm_set_vbus(port, true);
if (ret < 0)
goto out_disable_vconn;
+ ret = tcpm_set_roles(port, true, TYPEC_STATE_USB, TYPEC_SOURCE,
+ tcpm_data_role_for_source(port));
+ if (ret < 0)
+ goto out_disable_vbus;
+
+ if (port->pd_supported) {
+ ret = port->tcpc->set_pd_rx(port->tcpc, true);
+ if (ret < 0)
+ goto out_disable_mux;
+ }
+
port->pd_capable = false;
port->partner = NULL;
@@ -4447,14 +4447,14 @@ static int tcpm_src_attach(struct tcpm_port *port)
return 0;
-out_disable_vconn:
- tcpm_set_vconn(port, false);
-out_disable_pd:
- if (port->pd_supported)
- port->tcpc->set_pd_rx(port->tcpc, false);
out_disable_mux:
tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
TYPEC_ORIENTATION_NONE);
+out_disable_vbus:
+ tcpm_set_vbus(port, false);
+out_disable_vconn:
+ tcpm_set_vconn(port, false);
+
return ret;
}
If some config options are disabled during compile time, they still are
enumerated in macros that use the x86_capability bitmask - cpu_has() or
this_cpu_has().
The features are also visible in /proc/cpuinfo even though they are not
enabled - which is contrary to what the documentation states about the
file. Examples of such feature flags are lam, fred, sgx, ibrs_enhanced,
split_lock_detect, user_shstk, avx_vnni and enqcmd.
Add a DISABLED_MASK() macro that returns 32 bit chunks of the disabled
feature bits bitmask.
Initialize the cpu_caps_cleared and cpu_caps_set arrays with the
contents of the disabled and required bitmasks respectively. Then let
apply_forced_caps() clear/set these feature bits in the x86_capability.
Fixes: 6449dcb0cac7 ("x86: CPUID and CR3/CR4 flags for Linear Address Masking")
Fixes: 51c158f7aacc ("x86/cpufeatures: Add the CPU feature bit for FRED")
Fixes: 706d51681d63 ("x86/speculation: Support Enhanced IBRS on future CPUs")
Fixes: e7b6385b01d8 ("x86/cpufeatures: Add Intel SGX hardware bits")
Fixes: 6650cdd9a8cc ("x86/split_lock: Enable split lock detection by kernel")
Fixes: 701fb66d576e ("x86/cpufeatures: Add CPU feature flags for shadow stacks")
Fixes: ff4f82816dff ("x86/cpufeatures: Enumerate ENQCMD and ENQCMDS instructions")
Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com>
Cc: <stable(a)vger.kernel.org>
---
Changelog v2:
- Redo the patch to utilize a more generic solution, not just fix the
LAM and FRED feature bits.
- Note more feature flags that shouldn't be present.
- Add fixes and cc tags.
arch/x86/kernel/cpu/common.c | 12 ++++++++++++
arch/x86/tools/cpufeaturemasks.awk | 8 ++++++++
2 files changed, 20 insertions(+)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 77afca95cced..ba8b5fba8552 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1709,6 +1709,16 @@ static void __init cpu_parse_early_param(void)
}
}
+static __init void init_cpu_cap(struct cpuinfo_x86 *c)
+{
+ int i;
+
+ for (i = 0; i < NCAPINTS; i++) {
+ cpu_caps_set[i] = REQUIRED_MASK(i);
+ cpu_caps_cleared[i] = DISABLED_MASK(i);
+ }
+}
+
/*
* Do minimum CPU detection early.
* Fields really needed: vendor, cpuid_level, family, model, mask,
@@ -1782,6 +1792,8 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
if (!pgtable_l5_enabled())
setup_clear_cpu_cap(X86_FEATURE_LA57);
+ init_cpu_cap(c);
+
detect_nopl();
}
diff --git a/arch/x86/tools/cpufeaturemasks.awk b/arch/x86/tools/cpufeaturemasks.awk
index 173d5bf2d999..2e2412f7681f 100755
--- a/arch/x86/tools/cpufeaturemasks.awk
+++ b/arch/x86/tools/cpufeaturemasks.awk
@@ -82,6 +82,14 @@ END {
}
printf " 0\t\\\n";
printf "\t) & (1U << ((x) & 31)))\n\n";
+
+ printf "\n#define %s_MASK(x)\t\t\t\t\\\n", s;
+ printf "\t((\t\t\t\t";
+ for (i = 0; i < ncapints; i++) {
+ if (masks[i])
+ printf "\t\t\\\n\t\t(x) == %2d ? %s_MASK%d :", i, s, i;
+ }
+ printf " 0))\t\\\n\n";
}
printf "#endif /* _ASM_X86_CPUFEATUREMASKS_H */\n";
--
2.49.0
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 bec15191d52300defa282e3fd83820f69e447116
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025070814-resume-lazy-4b81@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bec15191d52300defa282e3fd83820f69e447116 Mon Sep 17 00:00:00 2001
From: RD Babiera <rdbabiera(a)google.com>
Date: Wed, 18 Jun 2025 23:06:04 +0000
Subject: [PATCH] usb: typec: tcpm: apply vbus before data bringup in
tcpm_src_attach
This patch fixes Type-C compliance test TD 4.7.6 - Try.SNK DRP Connect
SNKAS.
tVbusON has a limit of 275ms when entering SRC_ATTACHED. Compliance
testers can interpret the TryWait.Src to Attached.Src transition after
Try.Snk as being in Attached.Src the entire time, so ~170ms is lost
to the debounce timer.
Setting the data role can be a costly operation in host mode, and when
completed after 100ms can cause Type-C compliance test check TD 4.7.5.V.4
to fail.
Turn VBUS on before tcpm_set_roles to meet timing requirement.
Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable <stable(a)kernel.org>
Signed-off-by: RD Babiera <rdbabiera(a)google.com>
Reviewed-by: Badhri Jagan Sridharan <badhri(a)google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus(a)linux.intel.com>
Link: https://lore.kernel.org/r/20250618230606.3272497-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 1a1f9e1f8e4e..1f6fdfaa34bf 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4410,17 +4410,6 @@ static int tcpm_src_attach(struct tcpm_port *port)
tcpm_enable_auto_vbus_discharge(port, true);
- ret = tcpm_set_roles(port, true, TYPEC_STATE_USB,
- TYPEC_SOURCE, tcpm_data_role_for_source(port));
- if (ret < 0)
- return ret;
-
- if (port->pd_supported) {
- ret = port->tcpc->set_pd_rx(port->tcpc, true);
- if (ret < 0)
- goto out_disable_mux;
- }
-
/*
* USB Type-C specification, version 1.2,
* chapter 4.5.2.2.8.1 (Attached.SRC Requirements)
@@ -4430,13 +4419,24 @@ static int tcpm_src_attach(struct tcpm_port *port)
(polarity == TYPEC_POLARITY_CC2 && port->cc1 == TYPEC_CC_RA)) {
ret = tcpm_set_vconn(port, true);
if (ret < 0)
- goto out_disable_pd;
+ return ret;
}
ret = tcpm_set_vbus(port, true);
if (ret < 0)
goto out_disable_vconn;
+ ret = tcpm_set_roles(port, true, TYPEC_STATE_USB, TYPEC_SOURCE,
+ tcpm_data_role_for_source(port));
+ if (ret < 0)
+ goto out_disable_vbus;
+
+ if (port->pd_supported) {
+ ret = port->tcpc->set_pd_rx(port->tcpc, true);
+ if (ret < 0)
+ goto out_disable_mux;
+ }
+
port->pd_capable = false;
port->partner = NULL;
@@ -4447,14 +4447,14 @@ static int tcpm_src_attach(struct tcpm_port *port)
return 0;
-out_disable_vconn:
- tcpm_set_vconn(port, false);
-out_disable_pd:
- if (port->pd_supported)
- port->tcpc->set_pd_rx(port->tcpc, false);
out_disable_mux:
tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
TYPEC_ORIENTATION_NONE);
+out_disable_vbus:
+ tcpm_set_vbus(port, false);
+out_disable_vconn:
+ tcpm_set_vconn(port, false);
+
return ret;
}
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 bec15191d52300defa282e3fd83820f69e447116
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025070813-unwoven-idealness-eaa2@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bec15191d52300defa282e3fd83820f69e447116 Mon Sep 17 00:00:00 2001
From: RD Babiera <rdbabiera(a)google.com>
Date: Wed, 18 Jun 2025 23:06:04 +0000
Subject: [PATCH] usb: typec: tcpm: apply vbus before data bringup in
tcpm_src_attach
This patch fixes Type-C compliance test TD 4.7.6 - Try.SNK DRP Connect
SNKAS.
tVbusON has a limit of 275ms when entering SRC_ATTACHED. Compliance
testers can interpret the TryWait.Src to Attached.Src transition after
Try.Snk as being in Attached.Src the entire time, so ~170ms is lost
to the debounce timer.
Setting the data role can be a costly operation in host mode, and when
completed after 100ms can cause Type-C compliance test check TD 4.7.5.V.4
to fail.
Turn VBUS on before tcpm_set_roles to meet timing requirement.
Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable <stable(a)kernel.org>
Signed-off-by: RD Babiera <rdbabiera(a)google.com>
Reviewed-by: Badhri Jagan Sridharan <badhri(a)google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus(a)linux.intel.com>
Link: https://lore.kernel.org/r/20250618230606.3272497-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 1a1f9e1f8e4e..1f6fdfaa34bf 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4410,17 +4410,6 @@ static int tcpm_src_attach(struct tcpm_port *port)
tcpm_enable_auto_vbus_discharge(port, true);
- ret = tcpm_set_roles(port, true, TYPEC_STATE_USB,
- TYPEC_SOURCE, tcpm_data_role_for_source(port));
- if (ret < 0)
- return ret;
-
- if (port->pd_supported) {
- ret = port->tcpc->set_pd_rx(port->tcpc, true);
- if (ret < 0)
- goto out_disable_mux;
- }
-
/*
* USB Type-C specification, version 1.2,
* chapter 4.5.2.2.8.1 (Attached.SRC Requirements)
@@ -4430,13 +4419,24 @@ static int tcpm_src_attach(struct tcpm_port *port)
(polarity == TYPEC_POLARITY_CC2 && port->cc1 == TYPEC_CC_RA)) {
ret = tcpm_set_vconn(port, true);
if (ret < 0)
- goto out_disable_pd;
+ return ret;
}
ret = tcpm_set_vbus(port, true);
if (ret < 0)
goto out_disable_vconn;
+ ret = tcpm_set_roles(port, true, TYPEC_STATE_USB, TYPEC_SOURCE,
+ tcpm_data_role_for_source(port));
+ if (ret < 0)
+ goto out_disable_vbus;
+
+ if (port->pd_supported) {
+ ret = port->tcpc->set_pd_rx(port->tcpc, true);
+ if (ret < 0)
+ goto out_disable_mux;
+ }
+
port->pd_capable = false;
port->partner = NULL;
@@ -4447,14 +4447,14 @@ static int tcpm_src_attach(struct tcpm_port *port)
return 0;
-out_disable_vconn:
- tcpm_set_vconn(port, false);
-out_disable_pd:
- if (port->pd_supported)
- port->tcpc->set_pd_rx(port->tcpc, false);
out_disable_mux:
tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
TYPEC_ORIENTATION_NONE);
+out_disable_vbus:
+ tcpm_set_vbus(port, false);
+out_disable_vconn:
+ tcpm_set_vconn(port, false);
+
return ret;
}
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 bec15191d52300defa282e3fd83820f69e447116
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025070813-antidote-uncoated-dabd@gregkh' --subject-prefix 'PATCH 6.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From bec15191d52300defa282e3fd83820f69e447116 Mon Sep 17 00:00:00 2001
From: RD Babiera <rdbabiera(a)google.com>
Date: Wed, 18 Jun 2025 23:06:04 +0000
Subject: [PATCH] usb: typec: tcpm: apply vbus before data bringup in
tcpm_src_attach
This patch fixes Type-C compliance test TD 4.7.6 - Try.SNK DRP Connect
SNKAS.
tVbusON has a limit of 275ms when entering SRC_ATTACHED. Compliance
testers can interpret the TryWait.Src to Attached.Src transition after
Try.Snk as being in Attached.Src the entire time, so ~170ms is lost
to the debounce timer.
Setting the data role can be a costly operation in host mode, and when
completed after 100ms can cause Type-C compliance test check TD 4.7.5.V.4
to fail.
Turn VBUS on before tcpm_set_roles to meet timing requirement.
Fixes: f0690a25a140 ("staging: typec: USB Type-C Port Manager (tcpm)")
Cc: stable <stable(a)kernel.org>
Signed-off-by: RD Babiera <rdbabiera(a)google.com>
Reviewed-by: Badhri Jagan Sridharan <badhri(a)google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus(a)linux.intel.com>
Link: https://lore.kernel.org/r/20250618230606.3272497-2-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 1a1f9e1f8e4e..1f6fdfaa34bf 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4410,17 +4410,6 @@ static int tcpm_src_attach(struct tcpm_port *port)
tcpm_enable_auto_vbus_discharge(port, true);
- ret = tcpm_set_roles(port, true, TYPEC_STATE_USB,
- TYPEC_SOURCE, tcpm_data_role_for_source(port));
- if (ret < 0)
- return ret;
-
- if (port->pd_supported) {
- ret = port->tcpc->set_pd_rx(port->tcpc, true);
- if (ret < 0)
- goto out_disable_mux;
- }
-
/*
* USB Type-C specification, version 1.2,
* chapter 4.5.2.2.8.1 (Attached.SRC Requirements)
@@ -4430,13 +4419,24 @@ static int tcpm_src_attach(struct tcpm_port *port)
(polarity == TYPEC_POLARITY_CC2 && port->cc1 == TYPEC_CC_RA)) {
ret = tcpm_set_vconn(port, true);
if (ret < 0)
- goto out_disable_pd;
+ return ret;
}
ret = tcpm_set_vbus(port, true);
if (ret < 0)
goto out_disable_vconn;
+ ret = tcpm_set_roles(port, true, TYPEC_STATE_USB, TYPEC_SOURCE,
+ tcpm_data_role_for_source(port));
+ if (ret < 0)
+ goto out_disable_vbus;
+
+ if (port->pd_supported) {
+ ret = port->tcpc->set_pd_rx(port->tcpc, true);
+ if (ret < 0)
+ goto out_disable_mux;
+ }
+
port->pd_capable = false;
port->partner = NULL;
@@ -4447,14 +4447,14 @@ static int tcpm_src_attach(struct tcpm_port *port)
return 0;
-out_disable_vconn:
- tcpm_set_vconn(port, false);
-out_disable_pd:
- if (port->pd_supported)
- port->tcpc->set_pd_rx(port->tcpc, false);
out_disable_mux:
tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
TYPEC_ORIENTATION_NONE);
+out_disable_vbus:
+ tcpm_set_vbus(port, false);
+out_disable_vconn:
+ tcpm_set_vconn(port, false);
+
return ret;
}