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 081056dc00a27bccb55ccc3c6f230a3d5fd3f7e0
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062040-detection-sufferer-7865@gregkh' --subject-prefix 'PATCH 6.6.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);
Like s390 and the jailhouse hypervisor, LoongArch's PCI architecture
allows passing isolated PCI functions to a guest OS instance. So it is
possible that there is a multi-function device without function 0 for
the host or guest.
Allow probing such functions by adding a IS_ENABLED(CONFIG_LOONGARCH)
case in the hypervisor_isolated_pci_functions() helper.
This is similar to commit 189c6c33ff421def040b9 ("PCI: Extend isolated
function probing to s390").
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Huacai Chen <chenhuacai(a)loongson.cn>
---
include/linux/hypervisor.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/include/linux/hypervisor.h b/include/linux/hypervisor.h
index 9efbc54e35e5..be5417303ecf 100644
--- a/include/linux/hypervisor.h
+++ b/include/linux/hypervisor.h
@@ -37,6 +37,9 @@ static inline bool hypervisor_isolated_pci_functions(void)
if (IS_ENABLED(CONFIG_S390))
return true;
+ if (IS_ENABLED(CONFIG_LOONGARCH))
+ return true;
+
return jailhouse_paravirt();
}
--
2.47.1
The deadlock can occur due to a recursive lock acquisition of
`cros_typec_altmode_data::mutex`.
The call chain is as follows:
1. cros_typec_altmode_work() acquires the mutex
2. typec_altmode_vdm() -> dp_altmode_vdm() ->
3. typec_altmode_exit() -> cros_typec_altmode_exit()
4. cros_typec_altmode_exit() attempts to acquire the mutex again
To prevent this, defer the `typec_altmode_exit()` call by scheduling
it rather than calling it directly from within the mutex-protected
context.
Cc: stable(a)vger.kernel.org
Fixes: b4b38ffb38c9 ("usb: typec: displayport: Receive DP Status Update NAK request exit dp altmode")
Signed-off-by: Andrei Kuchynski <akuchynski(a)chromium.org>
---
drivers/usb/typec/altmodes/displayport.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c
index b09b58d7311d..2abbe4de3216 100644
--- a/drivers/usb/typec/altmodes/displayport.c
+++ b/drivers/usb/typec/altmodes/displayport.c
@@ -394,8 +394,7 @@ static int dp_altmode_vdm(struct typec_altmode *alt,
case CMDT_RSP_NAK:
switch (cmd) {
case DP_CMD_STATUS_UPDATE:
- if (typec_altmode_exit(alt))
- dev_err(&dp->alt->dev, "Exit Mode Failed!\n");
+ dp->state = DP_STATE_EXIT;
break;
case DP_CMD_CONFIGURE:
dp->data.conf = 0;
--
2.50.0.rc2.761.g2dc52ea45b-goog
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 94a263f981a3fa3d93f65c31e0fed0756736be43
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062018-joyfully-unmixable-8b37@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 94a263f981a3fa3d93f65c31e0fed0756736be43 Mon Sep 17 00:00:00 2001
From: Sibi Sankar <quic_sibis(a)quicinc.com>
Date: Tue, 29 Apr 2025 15:11:06 +0100
Subject: [PATCH] firmware: arm_scmi: Ensure that the message-id supports
fastchannel
Currently the perf and powercap protocol relies on the protocol domain
attributes, which just ensures that one fastchannel per domain, before
instantiating fastchannels for all possible message-ids. Fix this by
ensuring that each message-id supports fastchannel before initialization.
Logs:
| scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:0] - ret:-95. Using regular messaging
| scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:1] - ret:-95. Using regular messaging
| scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:2] - ret:-95. Using regular messaging
CC: stable(a)vger.kernel.org
Reported-by: Johan Hovold <johan+linaro(a)kernel.org>
Closes: https://lore.kernel.org/lkml/ZoQjAWse2YxwyRJv@hovoldconsulting.com/
Fixes: 6f9ea4dabd2d ("firmware: arm_scmi: Generalize the fast channel support")
Reviewed-by: Johan Hovold <johan+linaro(a)kernel.org>
Tested-by: Johan Hovold <johan+linaro(a)kernel.org>
Signed-off-by: Sibi Sankar <quic_sibis(a)quicinc.com>
[Cristian: Modified the condition checked to establish support or not]
Signed-off-by: Cristian Marussi <cristian.marussi(a)arm.com>
Message-Id: <20250429141108.406045-2-cristian.marussi(a)arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla(a)arm.com>
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 520aa5846916..cf2bc8b8d881 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -1729,6 +1729,39 @@ static int scmi_common_get_max_msg_size(const struct scmi_protocol_handle *ph)
return info->desc->max_msg_size;
}
+/**
+ * scmi_protocol_msg_check - Check protocol message attributes
+ *
+ * @ph: A reference to the protocol handle.
+ * @message_id: The ID of the message to check.
+ * @attributes: A parameter to optionally return the retrieved message
+ * attributes, in case of Success.
+ *
+ * An helper to check protocol message attributes for a specific protocol
+ * and message pair.
+ *
+ * Return: 0 on SUCCESS
+ */
+static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
+ u32 message_id, u32 *attributes)
+{
+ int ret;
+ struct scmi_xfer *t;
+
+ ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
+ sizeof(__le32), 0, &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(message_id, t->tx.buf);
+ ret = do_xfer(ph, t);
+ if (!ret && attributes)
+ *attributes = get_unaligned_le32(t->rx.buf);
+ xfer_put(ph, t);
+
+ return ret;
+}
+
/**
* struct scmi_iterator - Iterator descriptor
* @msg: A reference to the message TX buffer; filled by @prepare_message with
@@ -1870,6 +1903,7 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
int ret;
u32 flags;
u64 phys_addr;
+ u32 attributes;
u8 size;
void __iomem *addr;
struct scmi_xfer *t;
@@ -1878,6 +1912,15 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
struct scmi_msg_resp_desc_fc *resp;
const struct scmi_protocol_instance *pi = ph_to_pi(ph);
+ /* Check if the MSG_ID supports fastchannel */
+ ret = scmi_protocol_msg_check(ph, message_id, &attributes);
+ if (ret || !MSG_SUPPORTS_FASTCHANNEL(attributes)) {
+ dev_dbg(ph->dev,
+ "Skip FC init for 0x%02X/%d domain:%d - ret:%d\n",
+ pi->proto->id, message_id, domain, ret);
+ return;
+ }
+
if (!p_addr) {
ret = -EINVAL;
goto err_out;
@@ -1995,39 +2038,6 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
SCMI_PROTO_FC_RING_DB(64);
}
-/**
- * scmi_protocol_msg_check - Check protocol message attributes
- *
- * @ph: A reference to the protocol handle.
- * @message_id: The ID of the message to check.
- * @attributes: A parameter to optionally return the retrieved message
- * attributes, in case of Success.
- *
- * An helper to check protocol message attributes for a specific protocol
- * and message pair.
- *
- * Return: 0 on SUCCESS
- */
-static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
- u32 message_id, u32 *attributes)
-{
- int ret;
- struct scmi_xfer *t;
-
- ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
- sizeof(__le32), 0, &t);
- if (ret)
- return ret;
-
- put_unaligned_le32(message_id, t->tx.buf);
- ret = do_xfer(ph, t);
- if (!ret && attributes)
- *attributes = get_unaligned_le32(t->rx.buf);
- xfer_put(ph, t);
-
- return ret;
-}
-
static const struct scmi_proto_helpers_ops helpers_ops = {
.extended_name_get = scmi_common_extended_name_get,
.get_max_msg_size = scmi_common_get_max_msg_size,
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index aaee57cdcd55..d62c4469d1fd 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -31,6 +31,8 @@
#define SCMI_PROTOCOL_VENDOR_BASE 0x80
+#define MSG_SUPPORTS_FASTCHANNEL(x) ((x) & BIT(0))
+
enum scmi_common_cmd {
PROTOCOL_VERSION = 0x0,
PROTOCOL_ATTRIBUTES = 0x1,
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 94a263f981a3fa3d93f65c31e0fed0756736be43
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062017-daybreak-patronage-a6b4@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 94a263f981a3fa3d93f65c31e0fed0756736be43 Mon Sep 17 00:00:00 2001
From: Sibi Sankar <quic_sibis(a)quicinc.com>
Date: Tue, 29 Apr 2025 15:11:06 +0100
Subject: [PATCH] firmware: arm_scmi: Ensure that the message-id supports
fastchannel
Currently the perf and powercap protocol relies on the protocol domain
attributes, which just ensures that one fastchannel per domain, before
instantiating fastchannels for all possible message-ids. Fix this by
ensuring that each message-id supports fastchannel before initialization.
Logs:
| scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:0] - ret:-95. Using regular messaging
| scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:1] - ret:-95. Using regular messaging
| scmi: Failed to get FC for protocol 13 [MSG_ID:6 / RES_ID:2] - ret:-95. Using regular messaging
CC: stable(a)vger.kernel.org
Reported-by: Johan Hovold <johan+linaro(a)kernel.org>
Closes: https://lore.kernel.org/lkml/ZoQjAWse2YxwyRJv@hovoldconsulting.com/
Fixes: 6f9ea4dabd2d ("firmware: arm_scmi: Generalize the fast channel support")
Reviewed-by: Johan Hovold <johan+linaro(a)kernel.org>
Tested-by: Johan Hovold <johan+linaro(a)kernel.org>
Signed-off-by: Sibi Sankar <quic_sibis(a)quicinc.com>
[Cristian: Modified the condition checked to establish support or not]
Signed-off-by: Cristian Marussi <cristian.marussi(a)arm.com>
Message-Id: <20250429141108.406045-2-cristian.marussi(a)arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla(a)arm.com>
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 520aa5846916..cf2bc8b8d881 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -1729,6 +1729,39 @@ static int scmi_common_get_max_msg_size(const struct scmi_protocol_handle *ph)
return info->desc->max_msg_size;
}
+/**
+ * scmi_protocol_msg_check - Check protocol message attributes
+ *
+ * @ph: A reference to the protocol handle.
+ * @message_id: The ID of the message to check.
+ * @attributes: A parameter to optionally return the retrieved message
+ * attributes, in case of Success.
+ *
+ * An helper to check protocol message attributes for a specific protocol
+ * and message pair.
+ *
+ * Return: 0 on SUCCESS
+ */
+static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
+ u32 message_id, u32 *attributes)
+{
+ int ret;
+ struct scmi_xfer *t;
+
+ ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
+ sizeof(__le32), 0, &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(message_id, t->tx.buf);
+ ret = do_xfer(ph, t);
+ if (!ret && attributes)
+ *attributes = get_unaligned_le32(t->rx.buf);
+ xfer_put(ph, t);
+
+ return ret;
+}
+
/**
* struct scmi_iterator - Iterator descriptor
* @msg: A reference to the message TX buffer; filled by @prepare_message with
@@ -1870,6 +1903,7 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
int ret;
u32 flags;
u64 phys_addr;
+ u32 attributes;
u8 size;
void __iomem *addr;
struct scmi_xfer *t;
@@ -1878,6 +1912,15 @@ scmi_common_fastchannel_init(const struct scmi_protocol_handle *ph,
struct scmi_msg_resp_desc_fc *resp;
const struct scmi_protocol_instance *pi = ph_to_pi(ph);
+ /* Check if the MSG_ID supports fastchannel */
+ ret = scmi_protocol_msg_check(ph, message_id, &attributes);
+ if (ret || !MSG_SUPPORTS_FASTCHANNEL(attributes)) {
+ dev_dbg(ph->dev,
+ "Skip FC init for 0x%02X/%d domain:%d - ret:%d\n",
+ pi->proto->id, message_id, domain, ret);
+ return;
+ }
+
if (!p_addr) {
ret = -EINVAL;
goto err_out;
@@ -1995,39 +2038,6 @@ static void scmi_common_fastchannel_db_ring(struct scmi_fc_db_info *db)
SCMI_PROTO_FC_RING_DB(64);
}
-/**
- * scmi_protocol_msg_check - Check protocol message attributes
- *
- * @ph: A reference to the protocol handle.
- * @message_id: The ID of the message to check.
- * @attributes: A parameter to optionally return the retrieved message
- * attributes, in case of Success.
- *
- * An helper to check protocol message attributes for a specific protocol
- * and message pair.
- *
- * Return: 0 on SUCCESS
- */
-static int scmi_protocol_msg_check(const struct scmi_protocol_handle *ph,
- u32 message_id, u32 *attributes)
-{
- int ret;
- struct scmi_xfer *t;
-
- ret = xfer_get_init(ph, PROTOCOL_MESSAGE_ATTRIBUTES,
- sizeof(__le32), 0, &t);
- if (ret)
- return ret;
-
- put_unaligned_le32(message_id, t->tx.buf);
- ret = do_xfer(ph, t);
- if (!ret && attributes)
- *attributes = get_unaligned_le32(t->rx.buf);
- xfer_put(ph, t);
-
- return ret;
-}
-
static const struct scmi_proto_helpers_ops helpers_ops = {
.extended_name_get = scmi_common_extended_name_get,
.get_max_msg_size = scmi_common_get_max_msg_size,
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index aaee57cdcd55..d62c4469d1fd 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -31,6 +31,8 @@
#define SCMI_PROTOCOL_VENDOR_BASE 0x80
+#define MSG_SUPPORTS_FASTCHANNEL(x) ((x) & BIT(0))
+
enum scmi_common_cmd {
PROTOCOL_VERSION = 0x0,
PROTOCOL_ATTRIBUTES = 0x1,