[XEN PATCH v6 5/7] xen/x86: address violations of MISRA C:2012 Rule 7.2

Simone Ballarin posted 7 patches 5 months, 2 weeks ago
There is a newer version of this series
[XEN PATCH v6 5/7] xen/x86: address violations of MISRA C:2012 Rule 7.2
Posted by Simone Ballarin 5 months, 2 weeks ago
The xen sources contains violations of MISRA C:2012 Rule 7.2 whose
headline states:
"A 'u' or 'U' suffix shall be applied to all integer constants
that are represented in an unsigned type".

Add the 'U' suffix to integers literals with unsigned type.

For the sake of uniformity, the following change is made:
- add the 'U' suffix to switch cases in 'cpuid.c'

---
Changes in v6:
- new patch obtained by splitting X86 related changes from
"xen/x86: address violations of MISRA C:2012 Rule 7.2 (v5)"
---
 xen/arch/x86/apic.c       |  2 +-
 xen/arch/x86/cpu-policy.c | 18 +++++++++---------
 xen/arch/x86/cpuid.c      |  8 ++++----
 xen/arch/x86/extable.c    |  2 +-
 xen/arch/x86/percpu.c     |  2 +-
 xen/arch/x86/psr.c        |  2 +-
 xen/arch/x86/spec_ctrl.c  | 12 ++++++------
 7 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/xen/arch/x86/apic.c b/xen/arch/x86/apic.c
index 41879230ec..1109c0d9cf 100644
--- a/xen/arch/x86/apic.c
+++ b/xen/arch/x86/apic.c
@@ -1211,7 +1211,7 @@ static void __init calibrate_APIC_clock(void)
      * Setup the APIC counter to maximum. There is no way the lapic
      * can underflow in the 100ms detection time frame.
      */
-    __setup_APIC_LVTT(0xffffffff);
+    __setup_APIC_LVTT(0xffffffffU);
 
     bus_freq = calibrate_apic_timer();
     if ( !bus_freq )
diff --git a/xen/arch/x86/cpu-policy.c b/xen/arch/x86/cpu-policy.c
index 81e574390f..423932bc13 100644
--- a/xen/arch/x86/cpu-policy.c
+++ b/xen/arch/x86/cpu-policy.c
@@ -321,7 +321,7 @@ static void recalculate_misc(struct cpu_policy *p)
         p->extd.vendor_edx = p->basic.vendor_edx;
 
         p->extd.raw_fms = p->basic.raw_fms;
-        p->extd.raw[0x1].b &= 0xff00ffff;
+        p->extd.raw[0x1].b &= 0xff00ffffU;
         p->extd.e1d |= p->basic._1d & CPUID_COMMON_1D_FEATURES;
 
         p->extd.raw[0x8].a &= 0x0000ffff; /* GuestMaxPhysAddr hidden. */
@@ -378,10 +378,10 @@ static void __init calculate_host_policy(void)
      * this information.
      */
     if ( cpu_has_lfence_dispatch )
-        max_extd_leaf = max(max_extd_leaf, 0x80000021);
+        max_extd_leaf = max(max_extd_leaf, 0x80000021U);
 
-    p->extd.max_leaf = 0x80000000 | min_t(uint32_t, max_extd_leaf & 0xffff,
-                                          ARRAY_SIZE(p->extd.raw) - 1);
+    p->extd.max_leaf = 0x80000000U | min_t(uint32_t, max_extd_leaf & 0xffff,
+                                           ARRAY_SIZE(p->extd.raw) - 1);
 
     x86_cpu_featureset_to_policy(boot_cpu_data.x86_capability, p);
     recalculate_xstate(p);
@@ -793,11 +793,11 @@ void recalculate_cpuid_policy(struct domain *d)
 
     p->basic.max_leaf   = min(p->basic.max_leaf,   max->basic.max_leaf);
     p->feat.max_subleaf = min(p->feat.max_subleaf, max->feat.max_subleaf);
-    p->extd.max_leaf    = 0x80000000 | min(p->extd.max_leaf & 0xffff,
-                                           ((p->x86_vendor & (X86_VENDOR_AMD |
-                                                              X86_VENDOR_HYGON))
-                                            ? CPUID_GUEST_NR_EXTD_AMD
-                                            : CPUID_GUEST_NR_EXTD_INTEL) - 1);
+    p->extd.max_leaf    = 0x80000000U | min(p->extd.max_leaf & 0xffff,
+                                            ((p->x86_vendor & (X86_VENDOR_AMD |
+                                                               X86_VENDOR_HYGON))
+                                             ? CPUID_GUEST_NR_EXTD_AMD
+                                             : CPUID_GUEST_NR_EXTD_INTEL) - 1);
 
     x86_cpu_policy_to_featureset(p, fs);
     x86_cpu_policy_to_featureset(max, max_fs);
diff --git a/xen/arch/x86/cpuid.c b/xen/arch/x86/cpuid.c
index 455a09b2dd..7290a979c6 100644
--- a/xen/arch/x86/cpuid.c
+++ b/xen/arch/x86/cpuid.c
@@ -93,7 +93,7 @@ void guest_cpuid(const struct vcpu *v, uint32_t leaf,
         }
         break;
 
-    case 0x40000000 ... 0x400000ff:
+    case 0x40000000U ... 0x400000ffU:
         if ( is_viridian_domain(d) )
             return cpuid_viridian_leaves(v, leaf, subleaf, res);
 
@@ -103,10 +103,10 @@ void guest_cpuid(const struct vcpu *v, uint32_t leaf,
          * Intel reserve up until 0x4fffffff for hypervisor use.  AMD reserve
          * only until 0x400000ff, but we already use double that.
          */
-    case 0x40000100 ... 0x400001ff:
+    case 0x40000100U ... 0x400001ffU:
         return cpuid_hypervisor_leaves(v, leaf, subleaf, res);
 
-    case 0x80000000 ... 0x80000000 + CPUID_GUEST_NR_EXTD - 1:
+    case 0x80000000U ... 0x80000000U + CPUID_GUEST_NR_EXTD - 1:
         ASSERT((p->extd.max_leaf & 0xffff) < ARRAY_SIZE(p->extd.raw));
         if ( (leaf & 0xffff) > min_t(uint32_t, p->extd.max_leaf & 0xffff,
                                      ARRAY_SIZE(p->extd.raw) - 1) )
@@ -352,7 +352,7 @@ void guest_cpuid(const struct vcpu *v, uint32_t leaf,
         }
         break;
 
-    case 0x80000001:
+    case 0x80000001U:
         /* SYSCALL is hidden outside of long mode on Intel. */
         if ( p->x86_vendor == X86_VENDOR_INTEL &&
              is_hvm_domain(d) && !hvm_long_mode_active(v) )
diff --git a/xen/arch/x86/extable.c b/xen/arch/x86/extable.c
index 74b14246e9..652010f413 100644
--- a/xen/arch/x86/extable.c
+++ b/xen/arch/x86/extable.c
@@ -141,7 +141,7 @@ static int __init cf_check stub_selftest(void)
           .rax = 0x0123456789abcdef,
           .res.fields.trapnr = X86_EXC_GP },
         { .opc = { endbr64, 0x02, 0x04, 0x04, 0xc3 }, /* add (%rsp,%rax),%al */
-          .rax = 0xfedcba9876543210,
+          .rax = 0xfedcba9876543210UL,
           .res.fields.trapnr = X86_EXC_SS },
         { .opc = { endbr64, 0xcc, 0xc3, 0xc3, 0xc3 }, /* int3 */
           .res.fields.trapnr = X86_EXC_BP },
diff --git a/xen/arch/x86/percpu.c b/xen/arch/x86/percpu.c
index 288050cdba..1ebeb65ad6 100644
--- a/xen/arch/x86/percpu.c
+++ b/xen/arch/x86/percpu.c
@@ -12,7 +12,7 @@ unsigned long __per_cpu_offset[NR_CPUS];
  * possible #PF at (NULL + a little) which has security implications in the
  * context of PV guests.
  */
-#define INVALID_PERCPU_AREA (0x8000000000000000L - (long)__per_cpu_start)
+#define INVALID_PERCPU_AREA (0x8000000000000000UL - (long)__per_cpu_start)
 #define PERCPU_ORDER get_order_from_bytes(__per_cpu_data_end - __per_cpu_start)
 
 void __init percpu_init_areas(void)
diff --git a/xen/arch/x86/psr.c b/xen/arch/x86/psr.c
index 4c01813c4b..0b9631ac44 100644
--- a/xen/arch/x86/psr.c
+++ b/xen/arch/x86/psr.c
@@ -191,7 +191,7 @@ static struct feat_node *feat_l2_cat;
 static struct feat_node *feat_mba;
 
 /* Common functions */
-#define cat_default_val(len) (0xffffffff >> (32 - (len)))
+#define cat_default_val(len) (0xffffffffU >> (32 - (len)))
 
 /*
  * get_cdp_data - get DATA COS register value from input COS ID.
diff --git a/xen/arch/x86/spec_ctrl.c b/xen/arch/x86/spec_ctrl.c
index 9b8fdb5303..a3dec42f22 100644
--- a/xen/arch/x86/spec_ctrl.c
+++ b/xen/arch/x86/spec_ctrl.c
@@ -402,10 +402,10 @@ static void __init print_details(enum ind_thunk thunk)
         cpuid_count(7, 0, &max, &tmp, &tmp, &_7d0);
     if ( max >= 2 )
         cpuid_count(7, 2, &tmp, &tmp, &tmp, &_7d2);
-    if ( boot_cpu_data.extended_cpuid_level >= 0x80000008 )
-        cpuid(0x80000008, &tmp, &e8b, &tmp, &tmp);
-    if ( boot_cpu_data.extended_cpuid_level >= 0x80000021 )
-        cpuid(0x80000021, &e21a, &tmp, &tmp, &tmp);
+    if ( boot_cpu_data.extended_cpuid_level >= 0x80000008U )
+        cpuid(0x80000008U, &tmp, &e8b, &tmp, &tmp);
+    if ( boot_cpu_data.extended_cpuid_level >= 0x80000021U )
+        cpuid(0x80000021U, &e21a, &tmp, &tmp, &tmp);
     if ( cpu_has_arch_caps )
         rdmsrl(MSR_ARCH_CAPABILITIES, caps);
 
@@ -1568,8 +1568,8 @@ void __init init_speculation_mitigations(void)
          * TODO: Adjust cpu_has_svm_spec_ctrl to be usable earlier on boot.
          */
         if ( opt_msr_sc_hvm &&
-             (boot_cpu_data.extended_cpuid_level >= 0x8000000a) &&
-             (cpuid_edx(0x8000000a) & (1u << SVM_FEATURE_SPEC_CTRL)) )
+             (boot_cpu_data.extended_cpuid_level >= 0x8000000aU) &&
+             (cpuid_edx(0x8000000aU) & (1u << SVM_FEATURE_SPEC_CTRL)) )
             setup_force_cpu_cap(X86_FEATURE_SC_MSR_HVM);
     }
 
-- 
2.34.1
Re: [XEN PATCH v6 5/7] xen/x86: address violations of MISRA C:2012 Rule 7.2
Posted by Jan Beulich 5 months, 2 weeks ago
On 12.09.2023 17:39, Simone Ballarin wrote:
> --- a/xen/arch/x86/percpu.c
> +++ b/xen/arch/x86/percpu.c
> @@ -12,7 +12,7 @@ unsigned long __per_cpu_offset[NR_CPUS];
>   * possible #PF at (NULL + a little) which has security implications in the
>   * context of PV guests.
>   */
> -#define INVALID_PERCPU_AREA (0x8000000000000000L - (long)__per_cpu_start)
> +#define INVALID_PERCPU_AREA (0x8000000000000000UL - (long)__per_cpu_start)

Looking at this change the n-th , I can't help considering the result
inconsistent. Imo either the cast also wants changing, or the constant
wants to become -0x8000000000000000L (in whichever way is appropriate
to express it without violating any of the sometimes picky Misra rules;
maybe ~0x7fffffffffffffffL would work).

Jan
Re: [XEN PATCH v6 5/7] xen/x86: address violations of MISRA C:2012 Rule 7.2
Posted by Stefano Stabellini 5 months, 2 weeks ago
On Tue, 12 Sep 2023, Simone Ballarin wrote:
> The xen sources contains violations of MISRA C:2012 Rule 7.2 whose
> headline states:
> "A 'u' or 'U' suffix shall be applied to all integer constants
> that are represented in an unsigned type".
> 
> Add the 'U' suffix to integers literals with unsigned type.
> 
> For the sake of uniformity, the following change is made:
> - add the 'U' suffix to switch cases in 'cpuid.c'

Missing signed-off-by

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>