Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 1 | ========================================= |
| 2 | How to get printk format specifiers right |
| 3 | ========================================= |
| 4 | |
Ricardo CaƱuelo | 90c165f0 | 2020-04-03 11:36:17 +0200 | [diff] [blame] | 5 | .. _printk-specifiers: |
| 6 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 7 | :Author: Randy Dunlap <rdunlap@infradead.org> |
| 8 | :Author: Andrew Murray <amurray@mpc-data.co.uk> |
| 9 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 10 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 11 | Integer types |
| 12 | ============= |
| 13 | |
| 14 | :: |
| 15 | |
| 16 | If variable is of Type, use printk format specifier: |
| 17 | ------------------------------------------------------------ |
Andy Shevchenko | 243e212f | 2023-07-03 17:58:39 +0300 | [diff] [blame] | 18 | signed char %d or %hhx |
Joe Perches | cbacb5a | 2019-09-06 14:11:51 -0700 | [diff] [blame] | 19 | unsigned char %u or %x |
Andy Shevchenko | 243e212f | 2023-07-03 17:58:39 +0300 | [diff] [blame] | 20 | char %u or %x |
Andy Shevchenko | 46d57a7 | 2023-07-03 17:58:38 +0300 | [diff] [blame] | 21 | short int %d or %hx |
Joe Perches | cbacb5a | 2019-09-06 14:11:51 -0700 | [diff] [blame] | 22 | unsigned short int %u or %x |
Randy Dunlap | b67ad18 | 2008-11-12 13:26:55 -0800 | [diff] [blame] | 23 | int %d or %x |
| 24 | unsigned int %u or %x |
| 25 | long %ld or %lx |
| 26 | unsigned long %lu or %lx |
| 27 | long long %lld or %llx |
| 28 | unsigned long long %llu or %llx |
| 29 | size_t %zu or %zx |
| 30 | ssize_t %zd or %zx |
Andy Shevchenko | 46d57a7 | 2023-07-03 17:58:38 +0300 | [diff] [blame] | 31 | s8 %d or %hhx |
Joe Perches | cbacb5a | 2019-09-06 14:11:51 -0700 | [diff] [blame] | 32 | u8 %u or %x |
Andy Shevchenko | 46d57a7 | 2023-07-03 17:58:38 +0300 | [diff] [blame] | 33 | s16 %d or %hx |
Joe Perches | cbacb5a | 2019-09-06 14:11:51 -0700 | [diff] [blame] | 34 | u16 %u or %x |
Geert Uytterhoeven | e8a7ba5 | 2015-04-15 16:17:17 -0700 | [diff] [blame] | 35 | s32 %d or %x |
| 36 | u32 %u or %x |
| 37 | s64 %lld or %llx |
| 38 | u64 %llu or %llx |
| 39 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 40 | |
Carlos Llamas | d7c176e | 2021-06-09 19:50:58 +0000 | [diff] [blame] | 41 | If <type> is architecture-dependent for its size (e.g., cycles_t, tcflag_t) or |
| 42 | is dependent on a config option for its size (e.g., blk_status_t), use a format |
| 43 | specifier of its largest possible type and explicitly cast to it. |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 44 | |
| 45 | Example:: |
Geert Uytterhoeven | e8a7ba5 | 2015-04-15 16:17:17 -0700 | [diff] [blame] | 46 | |
Carlos Llamas | d7c176e | 2021-06-09 19:50:58 +0000 | [diff] [blame] | 47 | printk("test: latency: %llu cycles\n", (unsigned long long)time); |
Geert Uytterhoeven | e8a7ba5 | 2015-04-15 16:17:17 -0700 | [diff] [blame] | 48 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 49 | Reminder: sizeof() returns type size_t. |
Geert Uytterhoeven | e8a7ba5 | 2015-04-15 16:17:17 -0700 | [diff] [blame] | 50 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 51 | The kernel's printf does not support %n. Floating point formats (%e, %f, |
| 52 | %g, %a) are also not recognized, for obvious reasons. Use of any |
Rasmus Villemoes | d7ec9a0 | 2015-11-06 16:30:35 -0800 | [diff] [blame] | 53 | unsupported specifier or length qualifier results in a WARN and early |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 54 | return from vsnprintf(). |
Randy Dunlap | b67ad18 | 2008-11-12 13:26:55 -0800 | [diff] [blame] | 55 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 56 | Pointer types |
Tobin C. Harding | ad67b74 | 2017-11-01 15:32:23 +1100 | [diff] [blame] | 57 | ============= |
| 58 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 59 | A raw pointer value may be printed with %p which will hash the address |
| 60 | before printing. The kernel also supports extended specifiers for printing |
| 61 | pointers of different types. |
| 62 | |
Petr Mladek | 3e5903e | 2019-04-17 13:53:48 +0200 | [diff] [blame] | 63 | Some of the extended specifiers print the data on the given address instead |
| 64 | of printing the address itself. In this case, the following error messages |
| 65 | might be printed instead of the unreachable information:: |
| 66 | |
| 67 | (null) data on plain NULL address |
| 68 | (efault) data on invalid address |
Petr Mladek | 635720a | 2019-04-17 13:53:49 +0200 | [diff] [blame] | 69 | (einval) invalid data on a valid address |
Petr Mladek | 3e5903e | 2019-04-17 13:53:48 +0200 | [diff] [blame] | 70 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 71 | Plain Pointers |
| 72 | -------------- |
Tobin C. Harding | ad67b74 | 2017-11-01 15:32:23 +1100 | [diff] [blame] | 73 | |
| 74 | :: |
| 75 | |
| 76 | %p abcdef12 or 00000000abcdef12 |
| 77 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 78 | Pointers printed without a specifier extension (i.e unadorned %p) are |
| 79 | hashed to prevent leaking information about the kernel memory layout. This |
| 80 | has the added benefit of providing a unique identifier. On 64-bit machines |
Joel Stanley | 156383b | 2018-03-22 15:53:36 +1030 | [diff] [blame] | 81 | the first 32 bits are zeroed. The kernel will print ``(ptrval)`` until it |
Vlastimil Babka | a48849e | 2021-02-25 17:46:39 +0100 | [diff] [blame] | 82 | gathers enough entropy. |
| 83 | |
| 84 | When possible, use specialised modifiers such as %pS or %pB (described below) |
| 85 | to avoid the need of providing an unhashed address that has to be interpreted |
| 86 | post-hoc. If not possible, and the aim of printing the address is to provide |
| 87 | more information for debugging, use %p and boot the kernel with the |
| 88 | ``no_hash_pointers`` parameter during debugging, which will print all %p |
| 89 | addresses unmodified. If you *really* always want the unmodified address, see |
| 90 | %px below. |
| 91 | |
| 92 | If (and only if) you are printing addresses as a content of a virtual file in |
| 93 | e.g. procfs or sysfs (using e.g. seq_printf(), not printk()) read by a |
| 94 | userspace process, use the %pK modifier described below instead of %p or %px. |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 95 | |
Rasmus Villemoes | 57f5677 | 2019-10-15 21:07:05 +0200 | [diff] [blame] | 96 | Error Pointers |
| 97 | -------------- |
| 98 | |
| 99 | :: |
| 100 | |
| 101 | %pe -ENOSPC |
| 102 | |
| 103 | For printing error pointers (i.e. a pointer for which IS_ERR() is true) |
| 104 | as a symbolic error name. Error values for which no symbolic name is |
| 105 | known are printed in decimal, while a non-ERR_PTR passed as the |
| 106 | argument to %pe gets treated as ordinary %p. |
| 107 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 108 | Symbols/Function Pointers |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 109 | ------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 110 | |
| 111 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 112 | |
Sergey Senozhatsky | 04b8eb7 | 2017-12-06 13:36:49 +0900 | [diff] [blame] | 113 | %pS versatile_init+0x0/0x110 |
| 114 | %ps versatile_init |
Joe Perches | b0d33c2 | 2012-12-12 10:18:50 -0800 | [diff] [blame] | 115 | %pSR versatile_init+0x9/0x110 |
| 116 | (with __builtin_extract_return_addr() translation) |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 117 | %pB prev_fn_of_versatile_init+0x88/0x88 |
| 118 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 119 | |
Sergey Senozhatsky | 04b8eb7 | 2017-12-06 13:36:49 +0900 | [diff] [blame] | 120 | The ``S`` and ``s`` specifiers are used for printing a pointer in symbolic |
Linus Torvalds | ab486bc | 2018-02-01 13:36:15 -0800 | [diff] [blame] | 121 | format. They result in the symbol name with (S) or without (s) |
Sergey Senozhatsky | 04b8eb7 | 2017-12-06 13:36:49 +0900 | [diff] [blame] | 122 | offsets. If KALLSYMS are disabled then the symbol address is printed instead. |
Helge Deller | d6957f33 | 2017-08-15 11:34:19 +0200 | [diff] [blame] | 123 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 124 | The ``B`` specifier results in the symbol name with offsets and should be |
| 125 | used when printing stack backtraces. The specifier takes into |
| 126 | consideration the effect of compiler optimisations which may occur |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 127 | when tail-calls are used and marked with the noreturn GCC attribute. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 128 | |
Stephen Boyd | 9294523 | 2021-07-07 18:09:20 -0700 | [diff] [blame] | 129 | If the pointer is within a module, the module name and optionally build ID is |
| 130 | printed after the symbol name with an extra ``b`` appended to the end of the |
| 131 | specifier. |
| 132 | |
| 133 | :: |
Ioana Ciornei | 5b42d0b | 2021-07-22 13:03:53 +0300 | [diff] [blame] | 134 | |
Stephen Boyd | 9294523 | 2021-07-07 18:09:20 -0700 | [diff] [blame] | 135 | %pS versatile_init+0x0/0x110 [module_name] |
| 136 | %pSb versatile_init+0x0/0x110 [module_name ed5019fdf5e53be37cb1ba7899292d7e143b259e] |
| 137 | %pSRb versatile_init+0x9/0x110 [module_name ed5019fdf5e53be37cb1ba7899292d7e143b259e] |
| 138 | (with __builtin_extract_return_addr() translation) |
| 139 | %pBb prev_fn_of_versatile_init+0x88/0x88 [module_name ed5019fdf5e53be37cb1ba7899292d7e143b259e] |
| 140 | |
Daniel Borkmann | b2a5212 | 2020-05-15 12:11:18 +0200 | [diff] [blame] | 141 | Probed Pointers from BPF / tracing |
| 142 | ---------------------------------- |
| 143 | |
| 144 | :: |
| 145 | |
| 146 | %pks kernel string |
| 147 | %pus user string |
| 148 | |
| 149 | The ``k`` and ``u`` specifiers are used for printing prior probed memory from |
| 150 | either kernel memory (k) or user memory (u). The subsequent ``s`` specifier |
| 151 | results in printing a string. For direct use in regular vsnprintf() the (k) |
| 152 | and (u) annotation is ignored, however, when used out of BPF's bpf_trace_printk(), |
| 153 | for example, it reads the memory it is pointing to without faulting. |
| 154 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 155 | Kernel Pointers |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 156 | --------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 157 | |
| 158 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 159 | |
Tobin C. Harding | 553d8e8 | 2017-11-23 10:55:24 +1100 | [diff] [blame] | 160 | %pK 01234567 or 0123456789abcdef |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 161 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 162 | For printing kernel pointers which should be hidden from unprivileged |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 163 | users. The behaviour of %pK depends on the kptr_restrict sysctl - see |
Mauro Carvalho Chehab | 5704324 | 2019-04-22 16:48:00 -0300 | [diff] [blame] | 164 | Documentation/admin-guide/sysctl/kernel.rst for more details. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 165 | |
Vlastimil Babka | a48849e | 2021-02-25 17:46:39 +0100 | [diff] [blame] | 166 | This modifier is *only* intended when producing content of a file read by |
| 167 | userspace from e.g. procfs or sysfs, not for dmesg. Please refer to the |
| 168 | section about %p above for discussion about how to manage hashing pointers |
| 169 | in printk(). |
| 170 | |
Tobin C. Harding | 7b1924a | 2017-11-23 10:59:45 +1100 | [diff] [blame] | 171 | Unmodified Addresses |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 172 | -------------------- |
Tobin C. Harding | 7b1924a | 2017-11-23 10:59:45 +1100 | [diff] [blame] | 173 | |
| 174 | :: |
| 175 | |
| 176 | %px 01234567 or 0123456789abcdef |
| 177 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 178 | For printing pointers when you *really* want to print the address. Please |
Tobin C. Harding | 7b1924a | 2017-11-23 10:59:45 +1100 | [diff] [blame] | 179 | consider whether or not you are leaking sensitive information about the |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 180 | kernel memory layout before printing pointers with %px. %px is functionally |
| 181 | equivalent to %lx (or %lu). %px is preferred because it is more uniquely |
| 182 | grep'able. If in the future we need to modify the way the kernel handles |
| 183 | printing pointers we will be better equipped to find the call sites. |
Tobin C. Harding | 7b1924a | 2017-11-23 10:59:45 +1100 | [diff] [blame] | 184 | |
Vlastimil Babka | a48849e | 2021-02-25 17:46:39 +0100 | [diff] [blame] | 185 | Before using %px, consider if using %p is sufficient together with enabling the |
| 186 | ``no_hash_pointers`` kernel parameter during debugging sessions (see the %p |
| 187 | description above). One valid scenario for %px might be printing information |
| 188 | immediately before a panic, which prevents any sensitive information to be |
| 189 | exploited anyway, and with %px there would be no need to reproduce the panic |
| 190 | with no_hash_pointers. |
| 191 | |
Miles Chen | 88288ed | 2019-10-01 18:04:49 +0800 | [diff] [blame] | 192 | Pointer Differences |
| 193 | ------------------- |
| 194 | |
| 195 | :: |
| 196 | |
| 197 | %td 2560 |
| 198 | %tx a00 |
| 199 | |
| 200 | For printing the pointer differences, use the %t modifier for ptrdiff_t. |
| 201 | |
| 202 | Example:: |
| 203 | |
| 204 | printk("test: difference between pointers: %td\n", ptr2 - ptr1); |
| 205 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 206 | Struct Resources |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 207 | ---------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 208 | |
| 209 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 210 | |
| 211 | %pr [mem 0x60000000-0x6fffffff flags 0x2200] or |
| 212 | [mem 0x0000000060000000-0x000000006fffffff flags 0x2200] |
| 213 | %pR [mem 0x60000000-0x6fffffff pref] or |
| 214 | [mem 0x0000000060000000-0x000000006fffffff pref] |
| 215 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 216 | For printing struct resources. The ``R`` and ``r`` specifiers result in a |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 217 | printed resource with (R) or without (r) a decoded flags member. |
| 218 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 219 | Passed by reference. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 220 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 221 | Physical address types phys_addr_t |
| 222 | ---------------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 223 | |
| 224 | :: |
Stepan Moskovchenko | 7d79921 | 2013-02-21 16:43:09 -0800 | [diff] [blame] | 225 | |
Joe Perches | aaf0762 | 2014-01-23 15:54:17 -0800 | [diff] [blame] | 226 | %pa[p] 0x01234567 or 0x0123456789abcdef |
Stepan Moskovchenko | 7d79921 | 2013-02-21 16:43:09 -0800 | [diff] [blame] | 227 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 228 | For printing a phys_addr_t type (and its derivatives, such as |
| 229 | resource_size_t) which can vary based on build options, regardless of the |
| 230 | width of the CPU data path. |
Stepan Moskovchenko | 7d79921 | 2013-02-21 16:43:09 -0800 | [diff] [blame] | 231 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 232 | Passed by reference. |
| 233 | |
| 234 | DMA address types dma_addr_t |
| 235 | ---------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 236 | |
| 237 | :: |
Joe Perches | aaf0762 | 2014-01-23 15:54:17 -0800 | [diff] [blame] | 238 | |
| 239 | %pad 0x01234567 or 0x0123456789abcdef |
| 240 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 241 | For printing a dma_addr_t type which can vary based on build options, |
| 242 | regardless of the width of the CPU data path. |
| 243 | |
| 244 | Passed by reference. |
Joe Perches | aaf0762 | 2014-01-23 15:54:17 -0800 | [diff] [blame] | 245 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 246 | Raw buffer as an escaped string |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 247 | ------------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 248 | |
| 249 | :: |
Andy Shevchenko | 71dca95 | 2014-10-13 15:55:18 -0700 | [diff] [blame] | 250 | |
| 251 | %*pE[achnops] |
| 252 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 253 | For printing raw buffer as an escaped string. For the following buffer:: |
Andy Shevchenko | 71dca95 | 2014-10-13 15:55:18 -0700 | [diff] [blame] | 254 | |
| 255 | 1b 62 20 5c 43 07 22 90 0d 5d |
| 256 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 257 | A few examples show how the conversion would be done (excluding surrounding |
| 258 | quotes):: |
Andy Shevchenko | 71dca95 | 2014-10-13 15:55:18 -0700 | [diff] [blame] | 259 | |
| 260 | %*pE "\eb \C\a"\220\r]" |
| 261 | %*pEhp "\x1bb \C\x07"\x90\x0d]" |
| 262 | %*pEa "\e\142\040\\\103\a\042\220\r\135" |
| 263 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 264 | The conversion rules are applied according to an optional combination |
| 265 | of flags (see :c:func:`string_escape_mem` kernel documentation for the |
| 266 | details): |
Andy Shevchenko | 71dca95 | 2014-10-13 15:55:18 -0700 | [diff] [blame] | 267 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 268 | - a - ESCAPE_ANY |
| 269 | - c - ESCAPE_SPECIAL |
| 270 | - h - ESCAPE_HEX |
| 271 | - n - ESCAPE_NULL |
| 272 | - o - ESCAPE_OCTAL |
| 273 | - p - ESCAPE_NP |
| 274 | - s - ESCAPE_SPACE |
Andy Shevchenko | 71dca95 | 2014-10-13 15:55:18 -0700 | [diff] [blame] | 275 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 276 | By default ESCAPE_ANY_NP is used. |
Andy Shevchenko | 71dca95 | 2014-10-13 15:55:18 -0700 | [diff] [blame] | 277 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 278 | ESCAPE_ANY_NP is the sane choice for many cases, in particularly for |
| 279 | printing SSIDs. |
| 280 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 281 | If field width is omitted then 1 byte only will be escaped. |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 282 | |
| 283 | Raw buffer as a hex string |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 284 | -------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 285 | |
| 286 | :: |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 287 | |
Andy Shevchenko | 31550a1 | 2012-07-30 14:40:27 -0700 | [diff] [blame] | 288 | %*ph 00 01 02 ... 3f |
| 289 | %*phC 00:01:02: ... :3f |
| 290 | %*phD 00-01-02- ... -3f |
| 291 | %*phN 000102 ... 3f |
| 292 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 293 | For printing small buffers (up to 64 bytes long) as a hex string with a |
| 294 | certain separator. For larger buffers consider using |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 295 | :c:func:`print_hex_dump`. |
Andy Shevchenko | 31550a1 | 2012-07-30 14:40:27 -0700 | [diff] [blame] | 296 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 297 | MAC/FDDI addresses |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 298 | ------------------ |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 299 | |
| 300 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 301 | |
| 302 | %pM 00:01:02:03:04:05 |
Andrei Emeltchenko | 76597ff9 | 2012-07-30 14:40:23 -0700 | [diff] [blame] | 303 | %pMR 05:04:03:02:01:00 |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 304 | %pMF 00-01-02-03-04-05 |
| 305 | %pm 000102030405 |
Andy Shevchenko | 7c59154 | 2012-10-04 17:12:33 -0700 | [diff] [blame] | 306 | %pmR 050403020100 |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 307 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 308 | For printing 6-byte MAC/FDDI addresses in hex notation. The ``M`` and ``m`` |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 309 | specifiers result in a printed address with (M) or without (m) byte |
| 310 | separators. The default byte separator is the colon (:). |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 311 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 312 | Where FDDI addresses are concerned the ``F`` specifier can be used after |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 313 | the ``M`` specifier to use dash (-) separators instead of the default |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 314 | separator. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 315 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 316 | For Bluetooth addresses the ``R`` specifier shall be used after the ``M`` |
| 317 | specifier to use reversed byte order suitable for visual interpretation |
| 318 | of Bluetooth addresses which are in the little endian order. |
Andrei Emeltchenko | 76597ff9 | 2012-07-30 14:40:23 -0700 | [diff] [blame] | 319 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 320 | Passed by reference. |
Geert Uytterhoeven | 7330660 | 2015-04-15 16:17:14 -0700 | [diff] [blame] | 321 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 322 | IPv4 addresses |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 323 | -------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 324 | |
| 325 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 326 | |
| 327 | %pI4 1.2.3.4 |
| 328 | %pi4 001.002.003.004 |
Daniel Borkmann | 8ecada1 | 2013-06-28 15:49:39 +0200 | [diff] [blame] | 329 | %p[Ii]4[hnbl] |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 330 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 331 | For printing IPv4 dot-separated decimal addresses. The ``I4`` and ``i4`` |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 332 | specifiers result in a printed address with (i4) or without (I4) leading |
| 333 | zeros. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 334 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 335 | The additional ``h``, ``n``, ``b``, and ``l`` specifiers are used to specify |
| 336 | host, network, big or little endian order addresses respectively. Where |
| 337 | no specifier is provided the default network/big endian order is used. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 338 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 339 | Passed by reference. |
Geert Uytterhoeven | 7330660 | 2015-04-15 16:17:14 -0700 | [diff] [blame] | 340 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 341 | IPv6 addresses |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 342 | -------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 343 | |
| 344 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 345 | |
| 346 | %pI6 0001:0002:0003:0004:0005:0006:0007:0008 |
| 347 | %pi6 00010002000300040005000600070008 |
| 348 | %pI6c 1:2:3:4:5:6:7:8 |
| 349 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 350 | For printing IPv6 network-order 16-bit hex addresses. The ``I6`` and ``i6`` |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 351 | specifiers result in a printed address with (I6) or without (i6) |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 352 | colon-separators. Leading zeros are always used. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 353 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 354 | The additional ``c`` specifier can be used with the ``I`` specifier to |
| 355 | print a compressed IPv6 address as described by |
Alexander A. Klimov | 8eda94b | 2020-07-02 22:05:36 +0200 | [diff] [blame] | 356 | https://tools.ietf.org/html/rfc5952 |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 357 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 358 | Passed by reference. |
Geert Uytterhoeven | 7330660 | 2015-04-15 16:17:14 -0700 | [diff] [blame] | 359 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 360 | IPv4/IPv6 addresses (generic, with port, flowinfo, scope) |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 361 | --------------------------------------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 362 | |
| 363 | :: |
Daniel Borkmann | 1067964 | 2013-06-28 19:49:39 +0200 | [diff] [blame] | 364 | |
| 365 | %pIS 1.2.3.4 or 0001:0002:0003:0004:0005:0006:0007:0008 |
| 366 | %piS 001.002.003.004 or 00010002000300040005000600070008 |
| 367 | %pISc 1.2.3.4 or 1:2:3:4:5:6:7:8 |
| 368 | %pISpc 1.2.3.4:12345 or [1:2:3:4:5:6:7:8]:12345 |
| 369 | %p[Ii]S[pfschnbl] |
| 370 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 371 | For printing an IP address without the need to distinguish whether it's of |
| 372 | type AF_INET or AF_INET6. A pointer to a valid struct sockaddr, |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 373 | specified through ``IS`` or ``iS``, can be passed to this format specifier. |
Daniel Borkmann | 1067964 | 2013-06-28 19:49:39 +0200 | [diff] [blame] | 374 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 375 | The additional ``p``, ``f``, and ``s`` specifiers are used to specify port |
| 376 | (IPv4, IPv6), flowinfo (IPv6) and scope (IPv6). Ports have a ``:`` prefix, |
| 377 | flowinfo a ``/`` and scope a ``%``, each followed by the actual value. |
Daniel Borkmann | 1067964 | 2013-06-28 19:49:39 +0200 | [diff] [blame] | 378 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 379 | In case of an IPv6 address the compressed IPv6 address as described by |
Alexander A. Klimov | 8eda94b | 2020-07-02 22:05:36 +0200 | [diff] [blame] | 380 | https://tools.ietf.org/html/rfc5952 is being used if the additional |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 381 | specifier ``c`` is given. The IPv6 address is surrounded by ``[``, ``]`` in |
| 382 | case of additional specifiers ``p``, ``f`` or ``s`` as suggested by |
| 383 | https://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-07 |
Daniel Borkmann | 1067964 | 2013-06-28 19:49:39 +0200 | [diff] [blame] | 384 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 385 | In case of IPv4 addresses, the additional ``h``, ``n``, ``b``, and ``l`` |
| 386 | specifiers can be used as well and are ignored in case of an IPv6 |
| 387 | address. |
Daniel Borkmann | 1067964 | 2013-06-28 19:49:39 +0200 | [diff] [blame] | 388 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 389 | Passed by reference. |
Geert Uytterhoeven | 7330660 | 2015-04-15 16:17:14 -0700 | [diff] [blame] | 390 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 391 | Further examples:: |
Daniel Borkmann | 1067964 | 2013-06-28 19:49:39 +0200 | [diff] [blame] | 392 | |
| 393 | %pISfc 1.2.3.4 or [1:2:3:4:5:6:7:8]/123456789 |
| 394 | %pISsc 1.2.3.4 or [1:2:3:4:5:6:7:8]%1234567890 |
| 395 | %pISpfc 1.2.3.4:12345 or [1:2:3:4:5:6:7:8]:12345/123456789 |
| 396 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 397 | UUID/GUID addresses |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 398 | ------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 399 | |
| 400 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 401 | |
| 402 | %pUb 00010203-0405-0607-0809-0a0b0c0d0e0f |
| 403 | %pUB 00010203-0405-0607-0809-0A0B0C0D0E0F |
| 404 | %pUl 03020100-0504-0706-0809-0a0b0c0e0e0f |
| 405 | %pUL 03020100-0504-0706-0809-0A0B0C0E0E0F |
| 406 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 407 | For printing 16-byte UUID/GUIDs addresses. The additional ``l``, ``L``, |
| 408 | ``b`` and ``B`` specifiers are used to specify a little endian order in |
| 409 | lower (l) or upper case (L) hex notation - and big endian order in lower (b) |
| 410 | or upper case (B) hex notation. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 411 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 412 | Where no additional specifiers are used the default big endian |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 413 | order with lower case hex notation will be printed. |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 414 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 415 | Passed by reference. |
Geert Uytterhoeven | 7330660 | 2015-04-15 16:17:14 -0700 | [diff] [blame] | 416 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 417 | dentry names |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 418 | ------------ |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 419 | |
| 420 | :: |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 421 | |
Al Viro | 4b6ccca | 2013-09-03 12:00:44 -0400 | [diff] [blame] | 422 | %pd{,2,3,4} |
| 423 | %pD{,2,3,4} |
| 424 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 425 | For printing dentry name; if we race with :c:func:`d_move`, the name might |
| 426 | be a mix of old and new ones, but it won't oops. %pd dentry is a safer |
| 427 | equivalent of %s dentry->d_name.name we used to use, %pd<n> prints ``n`` |
| 428 | last components. %pD does the same thing for struct file. |
Al Viro | 4b6ccca | 2013-09-03 12:00:44 -0400 | [diff] [blame] | 429 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 430 | Passed by reference. |
Geert Uytterhoeven | 7330660 | 2015-04-15 16:17:14 -0700 | [diff] [blame] | 431 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 432 | block_device names |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 433 | ------------------ |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 434 | |
| 435 | :: |
Dmitry Monakhov | 1031bc5 | 2015-04-13 16:31:35 +0400 | [diff] [blame] | 436 | |
| 437 | %pg sda, sda1 or loop0p1 |
| 438 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 439 | For printing name of block_device pointers. |
Dmitry Monakhov | 1031bc5 | 2015-04-13 16:31:35 +0400 | [diff] [blame] | 440 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 441 | struct va_format |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 442 | ---------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 443 | |
| 444 | :: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 445 | |
| 446 | %pV |
| 447 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 448 | For printing struct va_format structures. These contain a format string |
| 449 | and va_list as follows:: |
Andrew Murray | 04c5571 | 2011-06-15 12:57:09 -0700 | [diff] [blame] | 450 | |
| 451 | struct va_format { |
| 452 | const char *fmt; |
| 453 | va_list *va; |
| 454 | }; |
| 455 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 456 | Implements a "recursive vsnprintf". |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 457 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 458 | Do not use this feature without some mechanism to verify the |
| 459 | correctness of the format string and va_list arguments. |
Randy Dunlap | b67ad18 | 2008-11-12 13:26:55 -0800 | [diff] [blame] | 460 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 461 | Passed by reference. |
Geert Uytterhoeven | 7330660 | 2015-04-15 16:17:14 -0700 | [diff] [blame] | 462 | |
Geert Uytterhoeven | 94ac8f2 | 2018-10-08 13:08:48 +0200 | [diff] [blame] | 463 | Device tree nodes |
| 464 | ----------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 465 | |
| 466 | :: |
| 467 | |
Pantelis Antoniou | ce4fecf | 2015-01-21 19:06:14 +0200 | [diff] [blame] | 468 | %pOF[fnpPcCF] |
| 469 | |
Pantelis Antoniou | ce4fecf | 2015-01-21 19:06:14 +0200 | [diff] [blame] | 470 | |
Geert Uytterhoeven | 94ac8f2 | 2018-10-08 13:08:48 +0200 | [diff] [blame] | 471 | For printing device tree node structures. Default behaviour is |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 472 | equivalent to %pOFf. |
| 473 | |
| 474 | - f - device node full_name |
| 475 | - n - device node name |
| 476 | - p - device node phandle |
| 477 | - P - device node path spec (name + @unit) |
| 478 | - F - device node flags |
| 479 | - c - major compatible string |
| 480 | - C - full compatible string |
| 481 | |
| 482 | The separator when using multiple arguments is ':' |
| 483 | |
| 484 | Examples:: |
Pantelis Antoniou | ce4fecf | 2015-01-21 19:06:14 +0200 | [diff] [blame] | 485 | |
| 486 | %pOF /foo/bar@0 - Node full name |
| 487 | %pOFf /foo/bar@0 - Same as above |
| 488 | %pOFfp /foo/bar@0:10 - Node full name + phandle |
| 489 | %pOFfcF /foo/bar@0:foo,device:--P- - Node full name + |
| 490 | major compatible string + |
| 491 | node flags |
| 492 | D - dynamic |
| 493 | d - detached |
| 494 | P - Populated |
| 495 | B - Populated bus |
| 496 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 497 | Passed by reference. |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 498 | |
Sakari Ailus | 3bd32d6 | 2019-10-03 15:32:18 +0300 | [diff] [blame] | 499 | Fwnode handles |
| 500 | -------------- |
| 501 | |
| 502 | :: |
| 503 | |
| 504 | %pfw[fP] |
| 505 | |
| 506 | For printing information on fwnode handles. The default is to print the full |
| 507 | node name, including the path. The modifiers are functionally equivalent to |
| 508 | %pOF above. |
| 509 | |
| 510 | - f - full name of the node, including the path |
| 511 | - P - the name of the node including an address (if there is one) |
| 512 | |
| 513 | Examples (ACPI):: |
| 514 | |
| 515 | %pfwf \_SB.PCI0.CIO2.port@1.endpoint@0 - Full node name |
| 516 | %pfwP endpoint@0 - Node name |
| 517 | |
| 518 | Examples (OF):: |
| 519 | |
| 520 | %pfwf /ocp@68000000/i2c@48072000/camera@10/port/endpoint - Full name |
| 521 | %pfwP endpoint - Node name |
| 522 | |
Andy Shevchenko | 7daac5b | 2020-04-15 20:00:44 +0300 | [diff] [blame] | 523 | Time and date |
| 524 | ------------- |
Andy Shevchenko | 4d42c44 | 2018-12-04 23:23:11 +0200 | [diff] [blame] | 525 | |
| 526 | :: |
| 527 | |
Andy Shevchenko | 7daac5b | 2020-04-15 20:00:44 +0300 | [diff] [blame] | 528 | %pt[RT] YYYY-mm-ddTHH:MM:SS |
Andy Shevchenko | 20bc8c1 | 2021-05-11 18:39:55 +0300 | [diff] [blame] | 529 | %pt[RT]s YYYY-mm-dd HH:MM:SS |
Andy Shevchenko | 7daac5b | 2020-04-15 20:00:44 +0300 | [diff] [blame] | 530 | %pt[RT]d YYYY-mm-dd |
| 531 | %pt[RT]t HH:MM:SS |
Andy Shevchenko | 20bc8c1 | 2021-05-11 18:39:55 +0300 | [diff] [blame] | 532 | %pt[RT][dt][r][s] |
Andy Shevchenko | 4d42c44 | 2018-12-04 23:23:11 +0200 | [diff] [blame] | 533 | |
Daniel W. S. Almeida | b7f4199 | 2020-07-18 13:51:02 -0300 | [diff] [blame] | 534 | For printing date and time as represented by:: |
| 535 | |
Andy Shevchenko | 7daac5b | 2020-04-15 20:00:44 +0300 | [diff] [blame] | 536 | R struct rtc_time structure |
| 537 | T time64_t type |
Daniel W. S. Almeida | b7f4199 | 2020-07-18 13:51:02 -0300 | [diff] [blame] | 538 | |
Andy Shevchenko | 7daac5b | 2020-04-15 20:00:44 +0300 | [diff] [blame] | 539 | in human readable format. |
Andy Shevchenko | 4d42c44 | 2018-12-04 23:23:11 +0200 | [diff] [blame] | 540 | |
Andy Shevchenko | 7daac5b | 2020-04-15 20:00:44 +0300 | [diff] [blame] | 541 | By default year will be incremented by 1900 and month by 1. |
| 542 | Use %pt[RT]r (raw) to suppress this behaviour. |
Andy Shevchenko | 4d42c44 | 2018-12-04 23:23:11 +0200 | [diff] [blame] | 543 | |
Andy Shevchenko | 20bc8c1 | 2021-05-11 18:39:55 +0300 | [diff] [blame] | 544 | The %pt[RT]s (space) will override ISO 8601 separator by using ' ' (space) |
| 545 | instead of 'T' (Capital T) between date and time. It won't have any effect |
| 546 | when date or time is omitted. |
| 547 | |
Andy Shevchenko | 4d42c44 | 2018-12-04 23:23:11 +0200 | [diff] [blame] | 548 | Passed by reference. |
| 549 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 550 | struct clk |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 551 | ---------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 552 | |
| 553 | :: |
Geert Uytterhoeven | 900cca2 | 2015-04-15 16:17:20 -0700 | [diff] [blame] | 554 | |
| 555 | %pC pll1 |
| 556 | %pCn pll1 |
Geert Uytterhoeven | 900cca2 | 2015-04-15 16:17:20 -0700 | [diff] [blame] | 557 | |
Geert Uytterhoeven | ec12bc2 | 2018-10-11 10:42:48 +0200 | [diff] [blame] | 558 | For printing struct clk structures. %pC and %pCn print the name of the clock |
| 559 | (Common Clock Framework) or a unique 32-bit ID (legacy clock framework). |
Geert Uytterhoeven | 900cca2 | 2015-04-15 16:17:20 -0700 | [diff] [blame] | 560 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 561 | Passed by reference. |
Geert Uytterhoeven | 900cca2 | 2015-04-15 16:17:20 -0700 | [diff] [blame] | 562 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 563 | bitmap and its derivatives such as cpumask and nodemask |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 564 | ------------------------------------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 565 | |
| 566 | :: |
Wang Long | d072496 | 2015-02-26 03:28:25 +0000 | [diff] [blame] | 567 | |
| 568 | %*pb 0779 |
| 569 | %*pbl 0,3-6,8-10 |
| 570 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 571 | For printing bitmap and its derivatives such as cpumask and nodemask, |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 572 | %*pb outputs the bitmap with field width as the number of bits and %*pbl |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 573 | output the bitmap as range list with field width as the number of bits. |
Wang Long | d072496 | 2015-02-26 03:28:25 +0000 | [diff] [blame] | 574 | |
Geert Uytterhoeven | 04d0608 | 2020-11-10 15:41:21 +0100 | [diff] [blame] | 575 | The field width is passed by value, the bitmap is passed by reference. |
| 576 | Helper macros cpumask_pr_args() and nodemask_pr_args() are available to ease |
| 577 | printing cpumask and nodemask. |
Randy Dunlap | b67ad18 | 2008-11-12 13:26:55 -0800 | [diff] [blame] | 578 | |
Hyeonggon Yoo | 4c85c0b | 2023-01-30 13:25:13 +0900 | [diff] [blame] | 579 | Flags bitfields such as page flags, page_type, gfp_flags |
| 580 | -------------------------------------------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 581 | |
| 582 | :: |
Vlastimil Babka | edf14cd | 2016-03-15 14:55:56 -0700 | [diff] [blame] | 583 | |
Petr Mladek | 6a7ca80 | 2021-10-27 14:48:40 +0200 | [diff] [blame] | 584 | %pGp 0x17ffffc0002036(referenced|uptodate|lru|active|private|node=0|zone=2|lastcpupid=0x1fffff) |
Hyeonggon Yoo | 4c85c0b | 2023-01-30 13:25:13 +0900 | [diff] [blame] | 585 | %pGt 0xffffff7f(buddy) |
Vlastimil Babka | edf14cd | 2016-03-15 14:55:56 -0700 | [diff] [blame] | 586 | %pGg GFP_USER|GFP_DMA32|GFP_NOWARN |
| 587 | %pGv read|exec|mayread|maywrite|mayexec|denywrite |
| 588 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 589 | For printing flags bitfields as a collection of symbolic constants that |
| 590 | would construct the value. The type of flags is given by the third |
Hyeonggon Yoo | 4c85c0b | 2023-01-30 13:25:13 +0900 | [diff] [blame] | 591 | character. Currently supported are: |
| 592 | |
| 593 | - p - [p]age flags, expects value of type (``unsigned long *``) |
| 594 | - t - page [t]ype, expects value of type (``unsigned int *``) |
| 595 | - v - [v]ma_flags, expects value of type (``unsigned long *``) |
| 596 | - g - [g]fp_flags, expects value of type (``gfp_t *``) |
| 597 | |
| 598 | The flag names and print order depends on the particular type. |
Vlastimil Babka | edf14cd | 2016-03-15 14:55:56 -0700 | [diff] [blame] | 599 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 600 | Note that this format should not be used directly in the |
| 601 | :c:func:`TP_printk()` part of a tracepoint. Instead, use the show_*_flags() |
| 602 | functions from <trace/events/mmflags.h>. |
Vlastimil Babka | edf14cd | 2016-03-15 14:55:56 -0700 | [diff] [blame] | 603 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 604 | Passed by reference. |
Vlastimil Babka | edf14cd | 2016-03-15 14:55:56 -0700 | [diff] [blame] | 605 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 606 | Network device features |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 607 | ----------------------- |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 608 | |
| 609 | :: |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 610 | |
| 611 | %pNF 0x000000000000c000 |
| 612 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 613 | For printing netdev_features_t. |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 614 | |
Mauro Carvalho Chehab | 3b03338 | 2017-05-16 22:27:11 -0300 | [diff] [blame] | 615 | Passed by reference. |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 616 | |
Sakari Ailus | af612e4 | 2021-02-16 17:57:20 +0200 | [diff] [blame] | 617 | V4L2 and DRM FourCC code (pixel format) |
| 618 | --------------------------------------- |
| 619 | |
| 620 | :: |
| 621 | |
| 622 | %p4cc |
| 623 | |
| 624 | Print a FourCC code used by V4L2 or DRM, including format endianness and |
| 625 | its numerical value as hexadecimal. |
| 626 | |
| 627 | Passed by reference. |
| 628 | |
| 629 | Examples:: |
| 630 | |
| 631 | %p4cc BG12 little-endian (0x32314742) |
| 632 | %p4cc Y10 little-endian (0x20303159) |
| 633 | %p4cc NV12 big-endian (0xb231564e) |
| 634 | |
Gary Guo | 787983d | 2021-07-03 17:38:57 +0200 | [diff] [blame] | 635 | Rust |
| 636 | ---- |
| 637 | |
| 638 | :: |
| 639 | |
| 640 | %pA |
| 641 | |
| 642 | Only intended to be used from Rust code to format ``core::fmt::Arguments``. |
| 643 | Do *not* use it from C. |
| 644 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 645 | Thanks |
| 646 | ====== |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 647 | |
Tobin C. Harding | b3ed232 | 2017-12-20 08:17:15 +1100 | [diff] [blame] | 648 | If you add other %p extensions, please extend <lib/test_printf.c> with |
| 649 | one or more test cases, if at all feasible. |
Martin Kletzander | 5e4ee7b | 2015-11-06 16:30:17 -0800 | [diff] [blame] | 650 | |
Randy Dunlap | b67ad18 | 2008-11-12 13:26:55 -0800 | [diff] [blame] | 651 | Thank you for your cooperation and attention. |