--- zzzz-none-000/linux-3.10.107/Documentation/printk-formats.txt 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/Documentation/printk-formats.txt 2021-02-04 17:41:59.000000000 +0000 @@ -8,6 +8,25 @@ unsigned long long %llu or %llx size_t %zu or %zx ssize_t %zd or %zx + s32 %d or %x + u32 %u or %x + s64 %lld or %llx + u64 %llu or %llx + +If is dependent on a config option for its size (e.g., sector_t, +blkcnt_t) or is architecture-dependent for its size (e.g., tcflag_t), use a +format specifier of its largest possible type and explicitly cast to it. +Example: + + printk("test: sector number/total blocks: %llu/%llu\n", + (unsigned long long)sector, (unsigned long long)blockcount); + +Reminder: sizeof() result is of type size_t. + +The kernel's printf does not support %n. For obvious reasons, floating +point formats (%e, %f, %g, %a) are also not recognized. Use of any +unsupported specifier or length qualifier results in a WARN and early +return from vsnprintf. Raw pointer value SHOULD be printed with %p. The kernel supports the following extended format specifiers for pointer types: @@ -54,16 +73,57 @@ For printing struct resources. The 'R' and 'r' specifiers result in a printed resource with ('R') or without ('r') a decoded flags member. + Passed by reference. -Physical addresses: +Physical addresses types phys_addr_t: - %pa 0x01234567 or 0x0123456789abcdef + %pa[p] 0x01234567 or 0x0123456789abcdef For printing a phys_addr_t type (and its derivatives, such as resource_size_t) which can vary based on build options, regardless of the width of the CPU data path. Passed by reference. +DMA addresses types dma_addr_t: + + %pad 0x01234567 or 0x0123456789abcdef + + For printing a dma_addr_t type which can vary based on build options, + regardless of the width of the CPU data path. Passed by reference. + +Raw buffer as an escaped string: + + %*pE[achnops] + + For printing raw buffer as an escaped string. For the following buffer + + 1b 62 20 5c 43 07 22 90 0d 5d + + few examples show how the conversion would be done (the result string + without surrounding quotes): + + %*pE "\eb \C\a"\220\r]" + %*pEhp "\x1bb \C\x07"\x90\x0d]" + %*pEa "\e\142\040\\\103\a\042\220\r\135" + + The conversion rules are applied according to an optional combination + of flags (see string_escape_mem() kernel documentation for the + details): + a - ESCAPE_ANY + c - ESCAPE_SPECIAL + h - ESCAPE_HEX + n - ESCAPE_NULL + o - ESCAPE_OCTAL + p - ESCAPE_NP + s - ESCAPE_SPACE + By default ESCAPE_ANY_NP is used. + + ESCAPE_ANY_NP is the sane choice for many cases, in particularly for + printing SSIDs. + + If field width is omitted the 1 byte only will be escaped. + Raw buffer as a hex string: + %*ph 00 01 02 ... 3f %*phC 00:01:02: ... :3f %*phD 00-01-02- ... -3f @@ -93,11 +153,13 @@ specifier to use reversed byte order suitable for visual interpretation of Bluetooth addresses which are in the little endian order. + Passed by reference. + IPv4 addresses: %pI4 1.2.3.4 %pi4 001.002.003.004 - %p[Ii][hnbl] + %p[Ii]4[hnbl] For printing IPv4 dot-separated decimal addresses. The 'I4' and 'i4' specifiers result in a printed address with ('i4') or without ('I4') @@ -107,6 +169,8 @@ host, network, big or little endian order addresses respectively. Where no specifier is provided the default network/big endian order is used. + Passed by reference. + IPv6 addresses: %pI6 0001:0002:0003:0004:0005:0006:0007:0008 @@ -121,6 +185,42 @@ print a compressed IPv6 address as described by http://tools.ietf.org/html/rfc5952 + Passed by reference. + +IPv4/IPv6 addresses (generic, with port, flowinfo, scope): + + %pIS 1.2.3.4 or 0001:0002:0003:0004:0005:0006:0007:0008 + %piS 001.002.003.004 or 00010002000300040005000600070008 + %pISc 1.2.3.4 or 1:2:3:4:5:6:7:8 + %pISpc 1.2.3.4:12345 or [1:2:3:4:5:6:7:8]:12345 + %p[Ii]S[pfschnbl] + + For printing an IP address without the need to distinguish whether it's + of type AF_INET or AF_INET6, a pointer to a valid 'struct sockaddr', + specified through 'IS' or 'iS', can be passed to this format specifier. + + The additional 'p', 'f', and 's' specifiers are used to specify port + (IPv4, IPv6), flowinfo (IPv6) and scope (IPv6). Ports have a ':' prefix, + flowinfo a '/' and scope a '%', each followed by the actual value. + + In case of an IPv6 address the compressed IPv6 address as described by + http://tools.ietf.org/html/rfc5952 is being used if the additional + specifier 'c' is given. The IPv6 address is surrounded by '[', ']' in + case of additional specifiers 'p', 'f' or 's' as suggested by + https://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-07 + + In case of IPv4 addresses, the additional 'h', 'n', 'b', and 'l' + specifiers can be used as well and are ignored in case of an IPv6 + address. + + Passed by reference. + + Further examples: + + %pISfc 1.2.3.4 or [1:2:3:4:5:6:7:8]/123456789 + %pISsc 1.2.3.4 or [1:2:3:4:5:6:7:8]%1234567890 + %pISpfc 1.2.3.4:12345 or [1:2:3:4:5:6:7:8]:12345/123456789 + UUID/GUID addresses: %pUb 00010203-0405-0607-0809-0a0b0c0d0e0f @@ -133,9 +233,23 @@ lower ('l') or upper case ('L') hex characters - and big endian order in lower ('b') or upper case ('B') hex characters. - Where no additional specifiers are used the default little endian + Where no additional specifiers are used the default big endian order with lower case hex characters will be printed. + Passed by reference. + +dentry names: + + %pd{,2,3,4} + %pD{,2,3,4} + + For printing dentry name; if we race with d_move(), the name might be + a mix of old and new ones, but it won't oops. %pd dentry is a safer + equivalent of %s dentry->d_name.name we used to use, %pd prints + n last components. %pD does the same thing for struct file. + + Passed by reference. + struct va_format: %pV @@ -148,26 +262,56 @@ va_list *va; }; + Implements a "recursive vsnprintf". + Do not use this feature without some mechanism to verify the correctness of the format string and va_list arguments. -u64 SHOULD be printed with %llu/%llx, (unsigned long long): + Passed by reference. - printk("%llu", (unsigned long long)u64_var); +struct clk: -s64 SHOULD be printed with %lld/%llx, (long long): + %pC pll1 + %pCn pll1 + %pCr 1560000000 - printk("%lld", (long long)s64_var); + For printing struct clk structures. '%pC' and '%pCn' print the name + (Common Clock Framework) or address (legacy clock framework) of the + structure; '%pCr' prints the current clock rate. -If is dependent on a config option for its size (e.g., sector_t, -blkcnt_t) or is architecture-dependent for its size (e.g., tcflag_t), use a -format specifier of its largest possible type and explicitly cast to it. -Example: + Passed by reference. - printk("test: sector number/total blocks: %llu/%llu\n", - (unsigned long long)sector, (unsigned long long)blockcount); +bitmap and its derivatives such as cpumask and nodemask: + + %*pb 0779 + %*pbl 0,3-6,8-10 + + For printing bitmap and its derivatives such as cpumask and nodemask, + %*pb output the bitmap with field width as the number of bits and %*pbl + output the bitmap as range list with field width as the number of bits. + + Passed by reference. + +Network device features: + + %pNF 0x000000000000c000 + + For printing netdev_features_t. + + Passed by reference. + +Command from struct task_struct + + %pT ls + + For printing executable name excluding path from struct + task_struct. + + Passed by reference. + +If you add other %p extensions, please extend lib/test_printf.c with +one or more test cases, if at all feasible. -Reminder: sizeof() result is of type size_t. Thank you for your cooperation and attention.