diff mbox series

[XEN,for-4.19,v6] xen: Add deviations for MISRA C:2012 Rule 7.1

Message ID 3646e75ebfc8b78d44578e3303bfa1660e0b684b.1699022991.git.nicola.vetrini@bugseng.com (mailing list archive)
State New, archived
Headers show
Series [XEN,for-4.19,v6] xen: Add deviations for MISRA C:2012 Rule 7.1 | expand

Commit Message

Nicola Vetrini Nov. 3, 2023, 2:50 p.m. UTC
As specified in rules.rst, these constants can be used
in the code.

Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
---
Changes in v2:
- replace some SAF deviations with configurations
Changes in v3:
- refine configurations and justifications
Changes in v4:
- updated deviation record comment.
Changes in v5:
- use octal-ok instead of keying the deviation to the file.
Changes in v6:
- use octal-ok everywhere; remove SAF-2-safe
---
 .../eclair_analysis/ECLAIR/deviations.ecl     |  7 ++--
 docs/misra/deviations.rst                     |  6 +++
 xen/arch/x86/hvm/svm/emulate.c                |  6 +--
 xen/arch/x86/hvm/svm/svm.h                    | 38 +++++++++----------
 xen/common/inflate.c                          |  4 +-
 5 files changed, 33 insertions(+), 28 deletions(-)

Comments

Stefano Stabellini Nov. 7, 2023, 4:18 a.m. UTC | #1
On Fri, 3 Nov 2023, Nicola Vetrini wrote:
> As specified in rules.rst, these constants can be used
> in the code.
> 
> Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
 
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Jan Beulich Nov. 13, 2023, 2:16 p.m. UTC | #2
On 07.11.2023 05:18, Stefano Stabellini wrote:
> On Fri, 3 Nov 2023, Nicola Vetrini wrote:
>> As specified in rules.rst, these constants can be used
>> in the code.
>>
>> Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
>  
> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

Acked-by: Jan Beulich <jbeulich@suse.com>
diff mbox series

Patch

diff --git a/automation/eclair_analysis/ECLAIR/deviations.ecl b/automation/eclair_analysis/ECLAIR/deviations.ecl
index fa56e5c00a27..fabbf9d66330 100644
--- a/automation/eclair_analysis/ECLAIR/deviations.ecl
+++ b/automation/eclair_analysis/ECLAIR/deviations.ecl
@@ -85,10 +85,9 @@  conform to the directive."
 # Series 7.
 #
 
--doc_begin="Usage of the following constants is safe, since they are given as-is
-in the inflate algorithm specification and there is therefore no risk of them
-being interpreted as decimal constants."
--config=MC3R1.R7.1,literals={safe, "^0(007|37|070|213|236|300|321|330|331|332|333|334|335|337|371)$"}
+-doc_begin="It is safe to use certain octal constants the way they are defined
+in specifications, manuals, and algorithm descriptions."
+-config=MC3R1.R7.1,reports+={safe, "any_area(any_loc(any_exp(text(^.*octal-ok.*$))))"}
 -doc_end
 
 -doc_begin="Violations in files that maintainers have asked to not modify in the
diff --git a/docs/misra/deviations.rst b/docs/misra/deviations.rst
index 8511a189253b..3a214d66eb37 100644
--- a/docs/misra/deviations.rst
+++ b/docs/misra/deviations.rst
@@ -90,6 +90,12 @@  Deviations related to MISRA C:2012 Rules:
          - __emulate_2op and __emulate_2op_nobyte
          - read_debugreg and write_debugreg
 
+   * - R7.1
+     - It is safe to use certain octal constants the way they are defined
+       in specifications, manuals, and algorithm descriptions. Such places
+       are marked safe with a /\* octal-ok \*/ in-code comment.
+     - Tagged as `safe` for ECLAIR.
+
    * - R7.2
      - Violations caused by __HYPERVISOR_VIRT_START are related to the
        particular use of it done in xen_mk_ulong.
diff --git a/xen/arch/x86/hvm/svm/emulate.c b/xen/arch/x86/hvm/svm/emulate.c
index aa2c61c433b3..93ac1d3435f9 100644
--- a/xen/arch/x86/hvm/svm/emulate.c
+++ b/xen/arch/x86/hvm/svm/emulate.c
@@ -90,9 +90,9 @@  unsigned int svm_get_insn_len(struct vcpu *v, unsigned int instr_enc)
         if ( !instr_modrm )
             return emul_len;
 
-        if ( modrm_mod       == MASK_EXTR(instr_modrm, 0300) &&
-             (modrm_reg & 7) == MASK_EXTR(instr_modrm, 0070) &&
-             (modrm_rm  & 7) == MASK_EXTR(instr_modrm, 0007) )
+        if ( modrm_mod       == MASK_EXTR(instr_modrm, 0300) && /* octal-ok */
+             (modrm_reg & 7) == MASK_EXTR(instr_modrm, 0070) && /* octal-ok */
+             (modrm_rm  & 7) == MASK_EXTR(instr_modrm, 0007) )  /* octal-ok */
             return emul_len;
     }
 
diff --git a/xen/arch/x86/hvm/svm/svm.h b/xen/arch/x86/hvm/svm/svm.h
index d2a781fc3fb5..8dbf37ff4961 100644
--- a/xen/arch/x86/hvm/svm/svm.h
+++ b/xen/arch/x86/hvm/svm/svm.h
@@ -53,25 +53,25 @@  static inline void svm_invlpga(unsigned long linear, uint32_t asid)
  */
 #define INSTR_ENC(opc, modrm) (((opc) << 8) | (modrm))
 
-#define INSTR_PAUSE       INSTR_ENC(X86EMUL_OPC_F3(0, 0x90), 0)
-#define INSTR_INT3        INSTR_ENC(X86EMUL_OPC(   0, 0xcc), 0)
-#define INSTR_ICEBP       INSTR_ENC(X86EMUL_OPC(   0, 0xf1), 0)
-#define INSTR_HLT         INSTR_ENC(X86EMUL_OPC(   0, 0xf4), 0)
-#define INSTR_XSETBV      INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0321)
-#define INSTR_VMRUN       INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0330)
-#define INSTR_VMCALL      INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0331)
-#define INSTR_VMLOAD      INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0332)
-#define INSTR_VMSAVE      INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0333)
-#define INSTR_STGI        INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0334)
-#define INSTR_CLGI        INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0335)
-#define INSTR_INVLPGA     INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0337)
-#define INSTR_RDTSCP      INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0371)
-#define INSTR_INVD        INSTR_ENC(X86EMUL_OPC(0x0f, 0x08), 0)
-#define INSTR_WBINVD      INSTR_ENC(X86EMUL_OPC(0x0f, 0x09), 0)
-#define INSTR_WRMSR       INSTR_ENC(X86EMUL_OPC(0x0f, 0x30), 0)
-#define INSTR_RDTSC       INSTR_ENC(X86EMUL_OPC(0x0f, 0x31), 0)
-#define INSTR_RDMSR       INSTR_ENC(X86EMUL_OPC(0x0f, 0x32), 0)
-#define INSTR_CPUID       INSTR_ENC(X86EMUL_OPC(0x0f, 0xa2), 0)
+#define INSTR_PAUSE      INSTR_ENC(X86EMUL_OPC_F3(0, 0x90), 0)
+#define INSTR_INT3       INSTR_ENC(X86EMUL_OPC(   0, 0xcc), 0)
+#define INSTR_ICEBP      INSTR_ENC(X86EMUL_OPC(   0, 0xf1), 0)
+#define INSTR_HLT        INSTR_ENC(X86EMUL_OPC(   0, 0xf4), 0)
+#define INSTR_XSETBV     INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0321) /* octal-ok */
+#define INSTR_VMRUN      INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0330) /* octal-ok */
+#define INSTR_VMCALL     INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0331) /* octal-ok */
+#define INSTR_VMLOAD     INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0332) /* octal-ok */
+#define INSTR_VMSAVE     INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0333) /* octal-ok */
+#define INSTR_STGI       INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0334) /* octal-ok */
+#define INSTR_CLGI       INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0335) /* octal-ok */
+#define INSTR_INVLPGA    INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0337) /* octal-ok */
+#define INSTR_RDTSCP     INSTR_ENC(X86EMUL_OPC(0x0f, 0x01), 0371) /* octal-ok */
+#define INSTR_INVD       INSTR_ENC(X86EMUL_OPC(0x0f, 0x08), 0)
+#define INSTR_WBINVD     INSTR_ENC(X86EMUL_OPC(0x0f, 0x09), 0)
+#define INSTR_WRMSR      INSTR_ENC(X86EMUL_OPC(0x0f, 0x30), 0)
+#define INSTR_RDTSC      INSTR_ENC(X86EMUL_OPC(0x0f, 0x31), 0)
+#define INSTR_RDMSR      INSTR_ENC(X86EMUL_OPC(0x0f, 0x32), 0)
+#define INSTR_CPUID      INSTR_ENC(X86EMUL_OPC(0x0f, 0xa2), 0)
 
 unsigned int svm_get_insn_len(struct vcpu *v, unsigned int instr_enc);
 unsigned int svm_get_task_switch_insn_len(void);
diff --git a/xen/common/inflate.c b/xen/common/inflate.c
index 8fa4b96d12a3..58f263d9e852 100644
--- a/xen/common/inflate.c
+++ b/xen/common/inflate.c
@@ -1201,8 +1201,8 @@  static int __init gunzip(void)
     magic[1] = NEXTBYTE();
     method   = NEXTBYTE();
 
-    if (magic[0] != 037 ||
-        ((magic[1] != 0213) && (magic[1] != 0236))) {
+    if (magic[0] != 037 ||                            /* octal-ok */
+        ((magic[1] != 0213) && (magic[1] != 0236))) { /* octal-ok */
         error("bad gzip magic numbers");
         return -1;
     }