ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 361 insertions, 0 deletions

diff --git a/drivers/hv/hv_trace.h b/drivers/hv/hv_trace.h
new file mode 100644
index 000000000..c02a1719e
--- /dev/null
+++ b/drivers/hv/hv_trace.h
@@ -0,0 +1,361 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM hyperv
+
+#if !defined(_HV_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _HV_TRACE_H
+
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(vmbus_hdr_msg,
+	TP_PROTO(const struct vmbus_channel_message_header *hdr),
+	TP_ARGS(hdr),
+	TP_STRUCT__entry(__field(unsigned int, msgtype)),
+	TP_fast_assign(__entry->msgtype = hdr->msgtype;),
+	TP_printk("msgtype=%u", __entry->msgtype)
+);
+
+DEFINE_EVENT(vmbus_hdr_msg, vmbus_on_msg_dpc,
+	TP_PROTO(const struct vmbus_channel_message_header *hdr),
+	TP_ARGS(hdr)
+);
+
+DEFINE_EVENT(vmbus_hdr_msg, vmbus_on_message,
+	TP_PROTO(const struct vmbus_channel_message_header *hdr),
+	TP_ARGS(hdr)
+);
+
+TRACE_EVENT(vmbus_onoffer,
+	    TP_PROTO(const struct vmbus_channel_offer_channel *offer),
+	    TP_ARGS(offer),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u8, monitorid)
+		    __field(u16, is_ddc_int)
+		    __field(u32, connection_id)
+		    __array(char, if_type, 16)
+		    __array(char, if_instance, 16)
+		    __field(u16, chn_flags)
+		    __field(u16, mmio_mb)
+		    __field(u16, sub_idx)
+		    ),
+	    TP_fast_assign(__entry->child_relid = offer->child_relid;
+			   __entry->monitorid = offer->monitorid;
+			   __entry->is_ddc_int = offer->is_dedicated_interrupt;
+			   __entry->connection_id = offer->connection_id;
+			   export_guid(__entry->if_type, &offer->offer.if_type);
+			   export_guid(__entry->if_instance, &offer->offer.if_instance);
+			   __entry->chn_flags = offer->offer.chn_flags;
+			   __entry->mmio_mb = offer->offer.mmio_megabytes;
+			   __entry->sub_idx = offer->offer.sub_channel_index;
+		    ),
+	    TP_printk("child_relid 0x%x, monitorid 0x%x, is_dedicated %d, "
+		      "connection_id 0x%x, if_type %pUl, if_instance %pUl, "
+		      "chn_flags 0x%x, mmio_megabytes %d, sub_channel_index %d",
+		      __entry->child_relid, __entry->monitorid,
+		      __entry->is_ddc_int, __entry->connection_id,
+		      __entry->if_type, __entry->if_instance,
+		      __entry->chn_flags, __entry->mmio_mb,
+		      __entry->sub_idx
+		    )
+	);
+
+TRACE_EVENT(vmbus_onoffer_rescind,
+	    TP_PROTO(const struct vmbus_channel_rescind_offer *offer),
+	    TP_ARGS(offer),
+	    TP_STRUCT__entry(__field(u32, child_relid)),
+	    TP_fast_assign(__entry->child_relid = offer->child_relid),
+	    TP_printk("child_relid 0x%x", __entry->child_relid)
+	);
+
+TRACE_EVENT(vmbus_onopen_result,
+	    TP_PROTO(const struct vmbus_channel_open_result *result),
+	    TP_ARGS(result),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u32, openid)
+		    __field(u32, status)
+		    ),
+	    TP_fast_assign(__entry->child_relid = result->child_relid;
+			   __entry->openid = result->openid;
+			   __entry->status = result->status;
+		    ),
+	    TP_printk("child_relid 0x%x, openid %d, status %d",
+		      __entry->child_relid,  __entry->openid,  __entry->status
+		    )
+	);
+
+TRACE_EVENT(vmbus_ongpadl_created,
+	    TP_PROTO(const struct vmbus_channel_gpadl_created *gpadlcreated),
+	    TP_ARGS(gpadlcreated),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u32, gpadl)
+		    __field(u32, status)
+		    ),
+	    TP_fast_assign(__entry->child_relid = gpadlcreated->child_relid;
+			   __entry->gpadl = gpadlcreated->gpadl;
+			   __entry->status = gpadlcreated->creation_status;
+		    ),
+	    TP_printk("child_relid 0x%x, gpadl 0x%x, creation_status %d",
+		      __entry->child_relid,  __entry->gpadl,  __entry->status
+		    )
+	);
+
+TRACE_EVENT(vmbus_onmodifychannel_response,
+	    TP_PROTO(const struct vmbus_channel_modifychannel_response *response),
+	    TP_ARGS(response),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u32, status)
+		    ),
+	    TP_fast_assign(__entry->child_relid = response->child_relid;
+			   __entry->status = response->status;
+		    ),
+	    TP_printk("child_relid 0x%x, status %d",
+		      __entry->child_relid,  __entry->status
+		    )
+	);
+
+TRACE_EVENT(vmbus_ongpadl_torndown,
+	    TP_PROTO(const struct vmbus_channel_gpadl_torndown *gpadltorndown),
+	    TP_ARGS(gpadltorndown),
+	    TP_STRUCT__entry(__field(u32, gpadl)),
+	    TP_fast_assign(__entry->gpadl = gpadltorndown->gpadl),
+	    TP_printk("gpadl 0x%x", __entry->gpadl)
+	);
+
+TRACE_EVENT(vmbus_onversion_response,
+	    TP_PROTO(const struct vmbus_channel_version_response *response),
+	    TP_ARGS(response),
+	    TP_STRUCT__entry(
+		    __field(u8, ver)
+		    ),
+	    TP_fast_assign(__entry->ver = response->version_supported;
+		    ),
+	    TP_printk("version_supported %d", __entry->ver)
+	);
+
+TRACE_EVENT(vmbus_request_offers,
+	    TP_PROTO(int ret),
+	    TP_ARGS(ret),
+	    TP_STRUCT__entry(__field(int, ret)),
+	    TP_fast_assign(__entry->ret = ret),
+	    TP_printk("sending ret %d", __entry->ret)
+	);
+
+TRACE_EVENT(vmbus_open,
+	    TP_PROTO(const struct vmbus_channel_open_channel *msg, int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u32, openid)
+		    __field(u32, gpadlhandle)
+		    __field(u32, target_vp)
+		    __field(u32, offset)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    __entry->child_relid = msg->child_relid;
+		    __entry->openid = msg->openid;
+		    __entry->gpadlhandle = msg->ringbuffer_gpadlhandle;
+		    __entry->target_vp = msg->target_vp;
+		    __entry->offset = msg->downstream_ringbuffer_pageoffset;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending child_relid 0x%x, openid %d, "
+		      "gpadlhandle 0x%x, target_vp 0x%x, offset 0x%x, ret %d",
+		      __entry->child_relid,  __entry->openid,
+		      __entry->gpadlhandle, __entry->target_vp,
+		      __entry->offset, __entry->ret
+		    )
+	);
+
+TRACE_EVENT(vmbus_close_internal,
+	    TP_PROTO(const struct vmbus_channel_close_channel *msg, int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    __entry->child_relid = msg->child_relid;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending child_relid 0x%x, ret %d", __entry->child_relid,
+		    __entry->ret)
+	);
+
+TRACE_EVENT(vmbus_establish_gpadl_header,
+	    TP_PROTO(const struct vmbus_channel_gpadl_header *msg, int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u32, gpadl)
+		    __field(u16, range_buflen)
+		    __field(u16, rangecount)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    __entry->child_relid = msg->child_relid;
+		    __entry->gpadl = msg->gpadl;
+		    __entry->range_buflen = msg->range_buflen;
+		    __entry->rangecount = msg->rangecount;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending child_relid 0x%x, gpadl 0x%x, range_buflen %d "
+		      "rangecount %d, ret %d",
+		      __entry->child_relid, __entry->gpadl,
+		      __entry->range_buflen, __entry->rangecount, __entry->ret
+		    )
+	);
+
+TRACE_EVENT(vmbus_establish_gpadl_body,
+	    TP_PROTO(const struct vmbus_channel_gpadl_body *msg, int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, msgnumber)
+		    __field(u32, gpadl)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    __entry->msgnumber = msg->msgnumber;
+		    __entry->gpadl = msg->gpadl;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending msgnumber %d, gpadl 0x%x, ret %d",
+		      __entry->msgnumber, __entry->gpadl, __entry->ret
+		    )
+	);
+
+TRACE_EVENT(vmbus_teardown_gpadl,
+	    TP_PROTO(const struct vmbus_channel_gpadl_teardown *msg, int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u32, gpadl)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    __entry->child_relid = msg->child_relid;
+		    __entry->gpadl = msg->gpadl;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending child_relid 0x%x, gpadl 0x%x, ret %d",
+		      __entry->child_relid, __entry->gpadl, __entry->ret
+		    )
+	);
+
+TRACE_EVENT(vmbus_negotiate_version,
+	    TP_PROTO(const struct vmbus_channel_initiate_contact *msg, int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, ver)
+		    __field(u32, target_vcpu)
+		    __field(int, ret)
+		    __field(u64, int_page)
+		    __field(u64, mon_page1)
+		    __field(u64, mon_page2)
+		    ),
+	    TP_fast_assign(
+		    __entry->ver = msg->vmbus_version_requested;
+		    __entry->target_vcpu = msg->target_vcpu;
+		    __entry->int_page = msg->interrupt_page;
+		    __entry->mon_page1 = msg->monitor_page1;
+		    __entry->mon_page2 = msg->monitor_page2;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending vmbus_version_requested %d, target_vcpu 0x%x, "
+		      "pages %llx:%llx:%llx, ret %d",
+		      __entry->ver, __entry->target_vcpu, __entry->int_page,
+		      __entry->mon_page1, __entry->mon_page2, __entry->ret
+		    )
+	);
+
+TRACE_EVENT(vmbus_release_relid,
+	    TP_PROTO(const struct vmbus_channel_relid_released *msg, int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    __entry->child_relid = msg->child_relid;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending child_relid 0x%x, ret %d",
+		      __entry->child_relid, __entry->ret
+		    )
+	);
+
+TRACE_EVENT(vmbus_send_tl_connect_request,
+	    TP_PROTO(const struct vmbus_channel_tl_connect_request *msg,
+		     int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __array(char, guest_id, 16)
+		    __array(char, host_id, 16)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    export_guid(__entry->guest_id, &msg->guest_endpoint_id);
+		    export_guid(__entry->host_id, &msg->host_service_id);
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("sending guest_endpoint_id %pUl, host_service_id %pUl, "
+		      "ret %d",
+		      __entry->guest_id, __entry->host_id, __entry->ret
+		    )
+	);
+
+TRACE_EVENT(vmbus_send_modifychannel,
+	    TP_PROTO(const struct vmbus_channel_modifychannel *msg,
+		     int ret),
+	    TP_ARGS(msg, ret),
+	    TP_STRUCT__entry(
+		    __field(u32, child_relid)
+		    __field(u32, target_vp)
+		    __field(int, ret)
+		    ),
+	    TP_fast_assign(
+		    __entry->child_relid = msg->child_relid;
+		    __entry->target_vp = msg->target_vp;
+		    __entry->ret = ret;
+		    ),
+	    TP_printk("binding child_relid 0x%x to target_vp 0x%x, ret %d",
+		      __entry->child_relid, __entry->target_vp, __entry->ret
+		    )
+	);
+
+DECLARE_EVENT_CLASS(vmbus_channel,
+	TP_PROTO(const struct vmbus_channel *channel),
+	TP_ARGS(channel),
+	TP_STRUCT__entry(__field(u32, relid)),
+	TP_fast_assign(__entry->relid = channel->offermsg.child_relid),
+	TP_printk("relid 0x%x", __entry->relid)
+);
+
+DEFINE_EVENT(vmbus_channel, vmbus_chan_sched,
+	    TP_PROTO(const struct vmbus_channel *channel),
+	    TP_ARGS(channel)
+);
+
+DEFINE_EVENT(vmbus_channel, vmbus_setevent,
+	    TP_PROTO(const struct vmbus_channel *channel),
+	    TP_ARGS(channel)
+);
+
+DEFINE_EVENT(vmbus_channel, vmbus_on_event,
+	    TP_PROTO(const struct vmbus_channel *channel),
+	    TP_ARGS(channel)
+);
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE hv_trace
+#endif /* _HV_TRACE_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>