[PATCH 19/65] xen/tasklet: Annotate fnptr targets

From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Xen-devel <xen-devel@lists.xenproject.org>
Cc: "Andrew Cooper" <andrew.cooper3@citrix.com>,
	"Jan Beulich" <JBeulich@suse.com>,
	"Stefano Stabellini" <sstabellini@kernel.org>,
	"Wei Liu" <wl@xen.org>, "Julien Grall" <julien@xen.org>,
	"Roger Pau Monné" <roger.pau@citrix.com>
Subject: [PATCH 19/65] xen/tasklet: Annotate fnptr targets
Date: Fri, 26 Nov 2021 12:34:00 +0000	[thread overview]
Message-ID: <20211126123446.32324-20-andrew.cooper3@citrix.com> (raw)
In-Reply-To: <20211126123446.32324-1-andrew.cooper3@citrix.com>

The function pointer cast in hvm_vcpu_initialise() is undefined behaviour.

While it happens to function correctly before this point, it is not
incompatible with control flow typechecking, so introduce a new
hvm_assert_evtchn_irq_tasklet() to handle the parameter type conversion in a
legal way.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Stefano Stabellini <sstabellini@kernel.org>
CC: Wei Liu <wl@xen.org>
CC: Julien Grall <julien@xen.org>
CC: Roger Pau Monné <roger.pau@citrix.com>
---
 xen/arch/x86/hvm/hvm.c                    | 7 ++++++-
 xen/arch/x86/hvm/vlapic.c                 | 2 +-
 xen/arch/x86/mm/shadow/common.c           | 2 +-
 xen/common/domain.c                       | 2 +-
 xen/common/keyhandler.c                   | 6 +++---
 xen/common/livepatch.c                    | 2 +-
 xen/common/stop_machine.c                 | 2 +-
 xen/common/trace.c                        | 2 +-
 xen/drivers/char/console.c                | 2 +-
 xen/drivers/passthrough/amd/iommu_guest.c | 2 +-
 xen/drivers/passthrough/amd/iommu_init.c  | 4 ++--
 xen/drivers/passthrough/arm/smmu-v3.c     | 6 +++---
 xen/drivers/passthrough/vtd/iommu.c       | 2 +-
 xen/include/asm-x86/shadow.h              | 2 +-
 14 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 0e935be1d772..16e8a32fa768 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -1540,6 +1540,11 @@ static int __init cf_check hvm_register_CPU_save_and_restore(void)
 }
 __initcall(hvm_register_CPU_save_and_restore);
 
+static void cf_check hvm_assert_evtchn_irq_tasklet(void *v)
+{
+    hvm_assert_evtchn_irq(v);
+}
+
 int hvm_vcpu_initialise(struct vcpu *v)
 {
     int rc;
@@ -1563,7 +1568,7 @@ int hvm_vcpu_initialise(struct vcpu *v)
         goto fail3;
 
     softirq_tasklet_init(&v->arch.hvm.assert_evtchn_irq_tasklet,
-                         (void (*)(void *))hvm_assert_evtchn_irq, v);
+                         hvm_assert_evtchn_irq_tasklet, v);
 
     v->arch.hvm.inject_event.vector = HVM_EVENT_VECTOR_UNSET;
 
diff --git a/xen/arch/x86/hvm/vlapic.c b/xen/arch/x86/hvm/vlapic.c
index b8c84458ffdc..fe375912bef1 100644
--- a/xen/arch/x86/hvm/vlapic.c
+++ b/xen/arch/x86/hvm/vlapic.c
@@ -312,7 +312,7 @@ static void vlapic_init_sipi_one(struct vcpu *target, uint32_t icr)
     vcpu_unpause(target);
 }
 
-static void vlapic_init_sipi_action(void *data)
+static void cf_check vlapic_init_sipi_action(void *data)
 {
     struct vcpu *origin = data;
     uint32_t icr = vcpu_vlapic(origin)->init_sipi.icr;
diff --git a/xen/arch/x86/mm/shadow/common.c b/xen/arch/x86/mm/shadow/common.c
index 1e4ee50771f5..b8cacbefef5f 100644
--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -3242,7 +3242,7 @@ void shadow_audit_tables(struct vcpu *v)
 
 #ifdef CONFIG_PV
 
-void pv_l1tf_tasklet(void *data)
+void cf_check pv_l1tf_tasklet(void *data)
 {
     struct domain *d = data;
 
diff --git a/xen/common/domain.c b/xen/common/domain.c
index a8b6ee59587c..4fcf9e23911f 100644
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -1833,7 +1833,7 @@ struct migrate_info {
 
 static DEFINE_PER_CPU(struct migrate_info *, continue_info);
 
-static void continue_hypercall_tasklet_handler(void *data)
+static void cf_check continue_hypercall_tasklet_handler(void *data)
 {
     struct migrate_info *info = data;
     struct vcpu *v = info->vcpu;
diff --git a/xen/common/keyhandler.c b/xen/common/keyhandler.c
index 2c916d528ab2..b568484ca62c 100644
--- a/xen/common/keyhandler.c
+++ b/xen/common/keyhandler.c
@@ -73,7 +73,7 @@ static struct keyhandler {
 #undef KEYHANDLER
 };
 
-static void keypress_action(void *unused)
+static void cf_check keypress_action(void *unused)
 {
     handle_keypress(keypress_key, NULL);
 }
@@ -206,7 +206,7 @@ static void dump_registers(unsigned char key, struct cpu_user_regs *regs)
 
 static DECLARE_TASKLET(dump_hwdom_tasklet, NULL, NULL);
 
-static void dump_hwdom_action(void *data)
+static void cf_check dump_hwdom_action(void *data)
 {
     struct vcpu *v = data;
 
@@ -437,7 +437,7 @@ static void read_clocks(unsigned char key)
            maxdif_cycles, sumdif_cycles/count, count, dif_cycles);
 }
 
-static void run_all_nonirq_keyhandlers(void *unused)
+static void cf_check run_all_nonirq_keyhandlers(void *unused)
 {
     /* Fire all the non-IRQ-context diagnostic keyhandlers */
     struct keyhandler *h;
diff --git a/xen/common/livepatch.c b/xen/common/livepatch.c
index 701efd87a173..4e1c29ab7879 100644
--- a/xen/common/livepatch.c
+++ b/xen/common/livepatch.c
@@ -1591,7 +1591,7 @@ static int schedule_work(struct payload *data, uint32_t cmd, uint32_t timeout)
     return 0;
 }
 
-static void tasklet_fn(void *unused)
+static void cf_check tasklet_fn(void *unused)
 {
     this_cpu(work_to_do) = 1;
 }
diff --git a/xen/common/stop_machine.c b/xen/common/stop_machine.c
index a122bd4afe09..3adbe380de96 100644
--- a/xen/common/stop_machine.c
+++ b/xen/common/stop_machine.c
@@ -141,7 +141,7 @@ int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu)
     return ret;
 }
 
-static void stopmachine_action(void *data)
+static void cf_check stopmachine_action(void *data)
 {
     unsigned int cpu = (unsigned long)data;
     enum stopmachine_state state = STOPMACHINE_START;
diff --git a/xen/common/trace.c b/xen/common/trace.c
index 0886be089bea..53978466cf92 100644
--- a/xen/common/trace.c
+++ b/xen/common/trace.c
@@ -663,7 +663,7 @@ static inline void insert_lost_records(struct t_buf *buf)
  * Notification is performed in qtasklet to avoid deadlocks with contexts
  * which __trace_var() may be called from (e.g., scheduler critical regions).
  */
-static void trace_notify_dom0(void *unused)
+static void cf_check trace_notify_dom0(void *unused)
 {
     send_global_virq(VIRQ_TBUF);
 }
diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c
index 4694be83db45..d74b65f6bf23 100644
--- a/xen/drivers/char/console.c
+++ b/xen/drivers/char/console.c
@@ -574,7 +574,7 @@ static void serial_rx(char c, struct cpu_user_regs *regs)
     __serial_rx(c, regs);
 }
 
-static void notify_dom0_con_ring(void *unused)
+static void cf_check notify_dom0_con_ring(void *unused)
 {
     send_global_virq(VIRQ_CON_RING);
 }
diff --git a/xen/drivers/passthrough/amd/iommu_guest.c b/xen/drivers/passthrough/amd/iommu_guest.c
index 85828490ffee..361ff864d846 100644
--- a/xen/drivers/passthrough/amd/iommu_guest.c
+++ b/xen/drivers/passthrough/amd/iommu_guest.c
@@ -456,7 +456,7 @@ static int do_invalidate_dte(struct domain *d, cmd_entry_t *cmd)
     return 0;
 }
 
-static void guest_iommu_process_command(void *data)
+static void cf_check guest_iommu_process_command(void *data)
 {
     unsigned long opcode, tail, head, cmd_mfn;
     cmd_entry_t *cmd;
diff --git a/xen/drivers/passthrough/amd/iommu_init.c b/xen/drivers/passthrough/amd/iommu_init.c
index f1ed75558227..34a9e49f1c5a 100644
--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -26,7 +26,7 @@
 static int __initdata nr_amd_iommus;
 static bool __initdata pci_init;
 
-static void do_amd_iommu_irq(void *data);
+static void cf_check do_amd_iommu_irq(void *data);
 static DECLARE_SOFTIRQ_TASKLET(amd_iommu_irq_tasklet, do_amd_iommu_irq, NULL);
 
 unsigned int __read_mostly amd_iommu_acpi_info;
@@ -692,7 +692,7 @@ static void iommu_check_ppr_log(struct amd_iommu *iommu)
     spin_unlock_irqrestore(&iommu->lock, flags);
 }
 
-static void do_amd_iommu_irq(void *unused)
+static void cf_check do_amd_iommu_irq(void *unused)
 {
     struct amd_iommu *iommu;
 
diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
index d115df732016..5e74266da21e 100644
--- a/xen/drivers/passthrough/arm/smmu-v3.c
+++ b/xen/drivers/passthrough/arm/smmu-v3.c
@@ -1475,7 +1475,7 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
 }
 
 /* IRQ and event handlers */
-static void arm_smmu_evtq_tasklet(void *dev)
+static void cf_check arm_smmu_evtq_tasklet(void *dev)
 {
 	int i;
 	struct arm_smmu_device *smmu = dev;
@@ -1545,7 +1545,7 @@ static void arm_smmu_handle_ppr(struct arm_smmu_device *smmu, u64 *evt)
 	}
 }
 
-static void arm_smmu_priq_tasklet(void *dev)
+static void cf_check arm_smmu_priq_tasklet(void *dev)
 {
 	struct arm_smmu_device *smmu = dev;
 	struct arm_smmu_queue *q = &smmu->priq.q;
@@ -1624,7 +1624,7 @@ static void arm_smmu_combined_irq_handler(int irq, void *dev,
 	tasklet_schedule(&(smmu->combined_irq_tasklet));
 }
 
-static void arm_smmu_combined_irq_tasklet(void *dev)
+static void cf_check arm_smmu_combined_irq_tasklet(void *dev)
 {
 	struct arm_smmu_device *smmu = dev;
 
diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index ba1ed5761d23..23519f2081bb 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -1065,7 +1065,7 @@ static void __do_iommu_page_fault(struct vtd_iommu *iommu)
     }
 }
 
-static void do_iommu_page_fault(void *unused)
+static void cf_check do_iommu_page_fault(void *unused)
 {
     struct acpi_drhd_unit *drhd;
 
diff --git a/xen/include/asm-x86/shadow.h b/xen/include/asm-x86/shadow.h
index e25f9604d896..7ef76cc0635b 100644
--- a/xen/include/asm-x86/shadow.h
+++ b/xen/include/asm-x86/shadow.h
@@ -233,7 +233,7 @@ static inline bool pv_l1tf_check_l4e(struct domain *d, l4_pgentry_t l4e)
     return pv_l1tf_check_pte(d, 4, l4e.l4);
 }
 
-void pv_l1tf_tasklet(void *data);
+void cf_check pv_l1tf_tasklet(void *data);
 
 static inline void pv_l1tf_domain_init(struct domain *d)
 {
-- 
2.11.0


