Re: [XEN PATCH v2 13/13] xen: fix violations of MISRA C:2012 Rule 7.2

[Simone Ballarin <simone.ballarin@xxxxxxxxxxx>]

Il giorno mer 5 lug 2023 alle ore 18:43 Luca Fancellu <Luca.Fancellu@xxxxxxx> ha scritto:

> On 5 Jul 2023, at 16:26, Simone Ballarin <simone.ballarin@xxxxxxxxxxx> wrote:
>
> From: Gianluca Luparini <gianluca.luparini@xxxxxxxxxxx>
>
> 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 and also to other
> literals used in the same contexts or near violations, when their positive
> nature is immediately clear. The latter changes are done for the sake of
> uniformity.
>
> Signed-off-by: Simone Ballarin <simone.ballarin@xxxxxxxxxxx>
> Signed-off-by: Gianluca Luparini <gianluca.luparini@xxxxxxxxxxx>
> ---
> Changes in v2:
> - minor change to commit title
> - change commit message
> - add '(uint32_t)' in 'muldiv64.c' for consistency
> - add fix in 'vesa.c'
> ---
> xen/common/gunzip.c          |  2 +-
> xen/common/xmalloc_tlsf.c    |  2 +-
> xen/drivers/char/ehci-dbgp.c |  4 ++--
> xen/drivers/video/vesa.c     |  2 +-
> xen/include/public/memory.h  |  2 +-
> xen/include/public/sysctl.h  |  4 ++--
> xen/include/xen/bitops.h     | 10 +++++-----
> xen/include/xen/cper.h       | 34 +++++++++++++++++-----------------
> xen/lib/muldiv64.c           |  2 +-
> 9 files changed, 31 insertions(+), 31 deletions(-)
>
> diff --git a/xen/common/gunzip.c b/xen/common/gunzip.c
> index 71ec5f26be..b810499be2 100644
> --- a/xen/common/gunzip.c
> +++ b/xen/common/gunzip.c
> @@ -11,7 +11,7 @@ static unsigned char *__initdata window;
> static memptr __initdata free_mem_ptr;
> static memptr __initdata free_mem_end_ptr;
>
> -#define WSIZE           0x80000000
> +#define WSIZE           0x80000000U
>
> static unsigned char *__initdata inbuf;
> static unsigned int __initdata insize;
> diff --git a/xen/common/xmalloc_tlsf.c b/xen/common/xmalloc_tlsf.c
> index 75bdf18c4e..c21bf71e88 100644
> --- a/xen/common/xmalloc_tlsf.c
> +++ b/xen/common/xmalloc_tlsf.c
> @@ -46,7 +46,7 @@
> #define BHDR_OVERHEAD   (sizeof(struct bhdr) - MIN_BLOCK_SIZE)
>
> #define PTR_MASK        (sizeof(void *) - 1)
> -#define BLOCK_SIZE_MASK (0xFFFFFFFF - PTR_MASK)
> +#define BLOCK_SIZE_MASK (0xFFFFFFFFU - PTR_MASK)
>
> #define GET_NEXT_BLOCK(addr, r) ((struct bhdr *) \
>                                 ((char *)(addr) + (r)))
> diff --git a/xen/drivers/char/ehci-dbgp.c b/xen/drivers/char/ehci-dbgp.c
> index bb9d3198d9..4d8d765122 100644
> --- a/xen/drivers/char/ehci-dbgp.c
> +++ b/xen/drivers/char/ehci-dbgp.c
> @@ -375,12 +375,12 @@ static inline u32 dbgp_pid_write_update(u32 x, u32 tok)
>     static u8 data0 = USB_PID_DATA1;
>
>     data0 ^= USB_PID_DATA0 ^ USB_PID_DATA1;
> -    return (x & 0xffff0000) | (data0 << 8) | (tok & 0xff);
> +    return (x & 0xffff0000U) | (data0 << 8) | (tok & 0xffU);
> }
>
> static inline u32 dbgp_pid_read_update(u32 x, u32 tok)
> {
> -    return (x & 0xffffff00) | (tok & 0xff);
> +    return (x & 0xffffff00U) | (tok & 0xffU);
> }
>
> static inline void dbgp_set_data(struct ehci_dbg_port __iomem *ehci_debug,
> diff --git a/xen/drivers/video/vesa.c b/xen/drivers/video/vesa.c
> index c41f6b8d40..b007ff5678 100644
> --- a/xen/drivers/video/vesa.c
> +++ b/xen/drivers/video/vesa.c
> @@ -123,7 +123,7 @@ void __init vesa_init(void)
>     if ( vlfb_info.bits_per_pixel > 8 )
>     {
>         /* Light grey in truecolor. */
> -        unsigned int grey = 0xaaaaaaaa;
> +        unsigned int grey = 0xaaaaaaaaU;
>         lfbp.pixel_on =
>             ((grey >> (32 - vlfb_info.  red_size)) << vlfb_info.  red_pos) |
>             ((grey >> (32 - vlfb_info.green_size)) << vlfb_info.green_pos) |
> diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h
> index c5f0d31e23..5e545ae9a4 100644
> --- a/xen/include/public/memory.h
> +++ b/xen/include/public/memory.h
> @@ -234,7 +234,7 @@ struct xen_add_to_physmap {
>
>     unsigned int space; /* => enum phys_map_space */
>
> -#define XENMAPIDX_grant_table_status 0x80000000
> +#define XENMAPIDX_grant_table_status 0x80000000U
>
>     /* Index into space being mapped. */
>     xen_ulong_t idx;
> diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h
> index 33e86ace51..fa7147de47 100644
> --- a/xen/include/public/sysctl.h
> +++ b/xen/include/public/sysctl.h
> @@ -384,7 +384,7 @@ struct xen_sysctl_pm_op {
>         struct xen_set_cpufreq_para set_para;
>         uint64_aligned_t get_avgfreq;
>         uint32_t                    set_sched_opt_smt;
> -#define XEN_SYSCTL_CX_UNLIMITED 0xffffffff
> +#define XEN_SYSCTL_CX_UNLIMITED 0xffffffffU
>         uint32_t                    get_max_cstate;
>         uint32_t                    set_max_cstate;
>     } u;
> @@ -547,7 +547,7 @@ struct xen_sysctl_numainfo {
> #define XEN_SYSCTL_CPUPOOL_OP_RMCPU                 5  /* R */
> #define XEN_SYSCTL_CPUPOOL_OP_MOVEDOMAIN            6  /* M */
> #define XEN_SYSCTL_CPUPOOL_OP_FREEINFO              7  /* F */
> -#define XEN_SYSCTL_CPUPOOL_PAR_ANY     0xFFFFFFFF
> +#define XEN_SYSCTL_CPUPOOL_PAR_ANY     0xFFFFFFFFU
> struct xen_sysctl_cpupool_op {
>     uint32_t op;          /* IN */
>     uint32_t cpupool_id;  /* IN: CDIARM OUT: CI */
> diff --git a/xen/include/xen/bitops.h b/xen/include/xen/bitops.h
> index 33619a0873..3b7e09a26e 100644
> --- a/xen/include/xen/bitops.h
> +++ b/xen/include/xen/bitops.h
> @@ -227,11 +227,11 @@ static inline __u32 ror32(__u32 word, unsigned int shift)
> }
>
> /* base-2 logarithm */
> -#define __L2(_x)  (((_x) & 0x00000002) ?   1 : 0)
> -#define __L4(_x)  (((_x) & 0x0000000c) ? ( 2 + __L2( (_x)>> 2)) : __L2( _x))
> -#define __L8(_x)  (((_x) & 0x000000f0) ? ( 4 + __L4( (_x)>> 4)) : __L4( _x))
> -#define __L16(_x) (((_x) & 0x0000ff00) ? ( 8 + __L8( (_x)>> 8)) : __L8( _x))
> -#define ilog2(_x) (((_x) & 0xffff0000) ? (16 + __L16((_x)>>16)) : __L16(_x))
> +#define __L2(_x)  (((_x) & 0x00000002U) ?   1 : 0)
> +#define __L4(_x)  (((_x) & 0x0000000cU) ? ( 2 + __L2( (_x)>> 2)) : __L2( _x))
> +#define __L8(_x)  (((_x) & 0x000000f0U) ? ( 4 + __L4( (_x)>> 4)) : __L4( _x))
> +#define __L16(_x) (((_x) & 0x0000ff00U) ? ( 8 + __L8( (_x)>> 8)) : __L8( _x))
> +#define ilog2(_x) (((_x) & 0xffff0000U) ? (16 + __L16((_x)>>16)) : __L16(_x))
>
> /**
>  * for_each_set_bit - iterate over every set bit in a memory region
> diff --git a/xen/include/xen/cper.h b/xen/include/xen/cper.h
> index f8e5272bc1..71d14faa02 100644
> --- a/xen/include/xen/cper.h
> +++ b/xen/include/xen/cper.h
> @@ -56,7 +56,7 @@ static inline uint64_t cper_next_record_id(void)
> #define CPER_SIG_RECORD "CPER"
> #define CPER_SIG_SIZE 4
> /* Used in signature_end field in struct cper_record_header */
> -#define CPER_SIG_END 0xffffffff
> +#define CPER_SIG_END 0xffffffffU
>
> /*
>  * CPER record header revision, used in revision field in struct
> @@ -80,36 +80,36 @@ static inline uint64_t cper_next_record_id(void)
>  * Corrected Machine Check
>  */
> #define CPER_NOTIFY_CMC \
> - UUID_LE(0x2DCE8BB1, 0xBDD7, 0x450e, 0xB9, 0xAD, 0x9C, 0xF4, \
> - 0xEB, 0xD4, 0xF8, 0x90)
> + UUID_LE(0x2DCE8BB1U, 0xBDD7U, 0x450eU, 0xB9U, 0xADU, 0x9CU, 0xF4U, \
> + 0xEBU, 0xD4U, 0xF8U, 0x90U)
> /* Corrected Platform Error */
> #define CPER_NOTIFY_CPE \
> - UUID_LE(0x4E292F96, 0xD843, 0x4a55, 0xA8, 0xC2, 0xD4, 0x81, \
> - 0xF2, 0x7E, 0xBE, 0xEE)
> + UUID_LE(0x4E292F96U, 0xD843U, 0x4a55U, 0xA8U, 0xC2U, 0xD4U, 0x81U, \
> + 0xF2U, 0x7EU, 0xBEU, 0xEEU)
> /* Machine Check Exception */
> #define CPER_NOTIFY_MCE \
> - UUID_LE(0xE8F56FFE, 0x919C, 0x4cc5, 0xBA, 0x88, 0x65, 0xAB, \
> - 0xE1, 0x49, 0x13, 0xBB)
> + UUID_LE(0xE8F56FFEU, 0x919CU, 0x4cc5U, 0xBAU, 0x88U, 0x65U, 0xABU, \
> + 0xE1U, 0x49U, 0x13U, 0xBBU)
> /* PCI Express Error */
> #define CPER_NOTIFY_PCIE \
> - UUID_LE(0xCF93C01F, 0x1A16, 0x4dfc, 0xB8, 0xBC, 0x9C, 0x4D, \
> - 0xAF, 0x67, 0xC1, 0x04)
> + UUID_LE(0xCF93C01FU, 0x1A16U, 0x4dfcU, 0xB8U, 0xBCU, 0x9CU, 0x4DU, \
> + 0xAFU, 0x67U, 0xC1U, 0x04U)
> /* INIT Record (for IPF) */
> #define CPER_NOTIFY_INIT \
> - UUID_LE(0xCC5263E8, 0x9308, 0x454a, 0x89, 0xD0, 0x34, 0x0B, \
> - 0xD3, 0x9B, 0xC9, 0x8E)
> + UUID_LE(0xCC5263E8U, 0x9308U, 0x454aU, 0x89U, 0xD0U, 0x34U, 0x0BU, \
> + 0xD3U, 0x9BU, 0xC9U, 0x8EU)
> /* Non-Maskable Interrupt */
> #define CPER_NOTIFY_NMI \
> - UUID_LE(0x5BAD89FF, 0xB7E6, 0x42c9, 0x81, 0x4A, 0xCF, 0x24, \
> - 0x85, 0xD6, 0xE9, 0x8A)
> + UUID_LE(0x5BAD89FFU, 0xB7E6U, 0x42c9U, 0x81U, 0x4AU, 0xCFU, 0x24U, \
> + 0x85U, 0xD6U, 0xE9U, 0x8AU)
> /* BOOT Error Record */
> #define CPER_NOTIFY_BOOT \
> - UUID_LE(0x3D61A466, 0xAB40, 0x409a, 0xA6, 0x98, 0xF3, 0x62, \
> - 0xD4, 0x64, 0xB3, 0x8F)
> + UUID_LE(0x3D61A466U, 0xAB40U, 0x409aU, 0xA6U, 0x98U, 0xF3U, 0x62U, \
> + 0xD4U, 0x64U, 0xB3U, 0x8FU)
> /* DMA Remapping Error */
> #define CPER_NOTIFY_DMAR \
> - UUID_LE(0x667DD791, 0xC6B3, 0x4c27, 0x8A, 0x6B, 0x0F, 0x8E, \
> - 0x72, 0x2D, 0xEB, 0x41)
> + UUID_LE(0x667DD791U, 0xC6B3U, 0x4c27U, 0x8AU, 0x6BU, 0x0FU, 0x8EU, \
> + 0x72U, 0x2DU, 0xEBU, 0x41U)
>
> /*
>  * Flags bits definitions for flags in struct cper_record_header
> diff --git a/xen/lib/muldiv64.c b/xen/lib/muldiv64.c
> index 78177ce616..e9bacc4c59 100644
> --- a/xen/lib/muldiv64.c
> +++ b/xen/lib/muldiv64.c
> @@ -27,7 +27,7 @@ uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c)
>     rh = (uint64_t)u.l.high * (uint64_t)b;
>     rh += (rl >> 32);
>     res.l.high = rh / c;
> -    res.l.low = (((rh % c) << 32) + (rl & 0xffffffff)) / c;
> +    res.l.low = (((rh % c) << 32) + ((uint32_t)rl & 0xffffffffU)) / c;

Why the explicit cast on rl? Shouldn’t it work without it?

Yes, the cast is not related to the MISRA rule.

It was requested by Jan in "[XEN PATCH 00/13] xen: fixed violations of MISRA C:2012 Rule 7.2"

to be more consistent with the surrounding code.

>
>     return res.ll;

--

Simone Ballarin, M.Sc.

Field Application Engineer, BUGSENG (https://bugseng.com)