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Diffstat (limited to 'src/kern/linux/helpers.cc')
| -rw-r--r-- | src/kern/linux/helpers.cc | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/src/kern/linux/helpers.cc b/src/kern/linux/helpers.cc new file mode 100644 index 000000000..54fc42138 --- /dev/null +++ b/src/kern/linux/helpers.cc @@ -0,0 +1,148 @@ +/* + * Copyright (c) 2016 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Andreas Sandberg + */ + +#include "kern/linux/helpers.hh" + +#include "arch/isa_traits.hh" +#include "config/the_isa.hh" +#include "cpu/thread_context.hh" +#include "mem/fs_translating_port_proxy.hh" +#include "sim/system.hh" + +struct DmesgEntry { + uint64_t ts_nsec; + uint16_t len; + uint16_t text_len; + uint16_t dict_len; + uint8_t facility; + uint8_t flags; +} M5_ATTR_PACKED; + +static int +dumpDmesgEntry(const uint8_t *base, const uint8_t *end, std::ostream &os) +{ + const size_t max_length = end - base; + DmesgEntry de; + + if (max_length < sizeof(de)) { + warn("Malformed dmesg entry\n"); + return -1; + } + + memcpy(&de, base, sizeof(de)); + de.ts_nsec = TheISA::gtoh(de.ts_nsec); + de.len = TheISA::gtoh(de.len); + de.text_len = TheISA::gtoh(de.text_len); + + if (de.len < sizeof(de) || + max_length < de.len || + max_length < sizeof(DmesgEntry) + de.text_len) { + + warn("Malformed dmesg entry:\n"); + warn("\tMax length: %i\n", max_length); + warn("\tde.len: %i\n", de.len); + warn("\tde.text_len: %i\n", de.text_len); + return -1; + } + + ccprintf(os, "[%.6f] ", de.ts_nsec * 10e-9); + os.write((char *)base + sizeof(de), de.text_len); + os << std::endl; + + return de.len; +} + +void +Linux::dumpDmesg(ThreadContext *tc, std::ostream &os) +{ + System *system = tc->getSystemPtr(); + const SymbolTable *symtab = system->kernelSymtab; + FSTranslatingPortProxy proxy(tc); + + Addr addr_lb = 0, addr_lb_len = 0, addr_first = 0, addr_next = 0; + const bool found_symbols = + symtab->findAddress("__log_buf", addr_lb) && + symtab->findAddress("log_buf_len", addr_lb_len) && + symtab->findAddress("log_first_idx", addr_first) && + symtab->findAddress("log_next_idx", addr_next); + + if (!found_symbols) { + warn("Failed to find kernel dmesg symbols.\n"); + return; + } + + uint32_t log_buf_len = proxy.readGtoH<uint32_t>(addr_lb_len); + uint32_t log_first_idx = proxy.readGtoH<uint32_t>(addr_first); + uint32_t log_next_idx = proxy.readGtoH<uint32_t>(addr_next); + + if (log_first_idx >= log_buf_len || log_next_idx >= log_buf_len) { + warn("dmesg pointers/length corrupted\n"); + return; + } + + // Normalize and read the dmesg ring buffer + std::vector<uint8_t> log_buf(log_buf_len); + int length; + if (log_first_idx < log_next_idx) { + length = log_next_idx - log_first_idx; + if (length < 0 || length > log_buf.size()) { + warn("Unexpected dmesg buffer length\n"); + return; + } + proxy.readBlob(addr_lb + log_first_idx, log_buf.data(), length); + } else { + const int length_2 = log_buf_len - log_first_idx; + if (length_2 < 0 || length_2 + log_next_idx > log_buf.size()) { + warn("Unexpected dmesg buffer length\n"); + return; + } + length = log_buf_len; + proxy.readBlob(addr_lb + log_first_idx, log_buf.data(), length_2); + proxy.readBlob(addr_lb, log_buf.data() + length_2, log_next_idx); + } + + // Print dmesg buffer content + const uint8_t *cur = log_buf.data(), *end = log_buf.data() + length; + while (cur < end) { + int ret = dumpDmesgEntry(cur, end, os); + if (ret < 0) + return; + cur += ret; + } +} |