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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-26 21:29:24 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-26 21:29:24 +0300 |
commit | 3ea54d9b0d655dab5b5becc7d6456082089fc166 (patch) | |
tree | bd70917f63bb752941157f62ff8f9201f2bde85b /Documentation/powerpc/ptrace.txt | |
parent | 0ed288665686a52781c0ff04ddfe402c7a5397e1 (diff) | |
parent | d2eba640a4b96bc1bdc0f4a500b8b8d5e16725c8 (diff) | |
download | linux-3ea54d9b0d655dab5b5becc7d6456082089fc166.tar.xz |
Merge tag 'docs-5.3-1' of git://git.lwn.net/linux
Pull documentation fixes from Jonathan Corbet:
"This is mostly a set of follow-on fixes from Mauro fixing various
fallout from the massive RST conversion; a few other small fixes as
well"
* tag 'docs-5.3-1' of git://git.lwn.net/linux: (21 commits)
docs: phy: Drop duplicate 'be made'
doc:it_IT: translations in process/
docs/vm: transhuge: fix typo in madvise reference
doc:it_IT: rephrase statement
doc:it_IT: align translation to mainline
docs: load_config.py: ensure subdirs end with "/"
docs: virtual: add it to the documentation body
docs: remove extra conf.py files
docs: load_config.py: avoid needing a conf.py just due to LaTeX docs
scripts/sphinx-pre-install: seek for Noto CJK fonts for pdf output
scripts/sphinx-pre-install: cleanup Gentoo checks
scripts/sphinx-pre-install: fix latexmk dependencies
scripts/sphinx-pre-install: don't use LaTeX with CentOS 7
scripts/sphinx-pre-install: fix script for RHEL/CentOS
docs: conf.py: only use CJK if the font is available
docs: conf.py: add CJK package needed by translations
docs: pdf: add all Documentation/*/index.rst to PDF output
docs: fix broken doc references due to renames
docs: power: add it to to the main documentation index
docs: powerpc: convert docs to ReST and rename to *.rst
...
Diffstat (limited to 'Documentation/powerpc/ptrace.txt')
-rw-r--r-- | Documentation/powerpc/ptrace.txt | 151 |
1 files changed, 0 insertions, 151 deletions
diff --git a/Documentation/powerpc/ptrace.txt b/Documentation/powerpc/ptrace.txt deleted file mode 100644 index 99c5ce88d0fe..000000000000 --- a/Documentation/powerpc/ptrace.txt +++ /dev/null @@ -1,151 +0,0 @@ -GDB intends to support the following hardware debug features of BookE -processors: - -4 hardware breakpoints (IAC) -2 hardware watchpoints (read, write and read-write) (DAC) -2 value conditions for the hardware watchpoints (DVC) - -For that, we need to extend ptrace so that GDB can query and set these -resources. Since we're extending, we're trying to create an interface -that's extendable and that covers both BookE and server processors, so -that GDB doesn't need to special-case each of them. We added the -following 3 new ptrace requests. - -1. PTRACE_PPC_GETHWDEBUGINFO - -Query for GDB to discover the hardware debug features. The main info to -be returned here is the minimum alignment for the hardware watchpoints. -BookE processors don't have restrictions here, but server processors have -an 8-byte alignment restriction for hardware watchpoints. We'd like to avoid -adding special cases to GDB based on what it sees in AUXV. - -Since we're at it, we added other useful info that the kernel can return to -GDB: this query will return the number of hardware breakpoints, hardware -watchpoints and whether it supports a range of addresses and a condition. -The query will fill the following structure provided by the requesting process: - -struct ppc_debug_info { - unit32_t version; - unit32_t num_instruction_bps; - unit32_t num_data_bps; - unit32_t num_condition_regs; - unit32_t data_bp_alignment; - unit32_t sizeof_condition; /* size of the DVC register */ - uint64_t features; /* bitmask of the individual flags */ -}; - -features will have bits indicating whether there is support for: - -#define PPC_DEBUG_FEATURE_INSN_BP_RANGE 0x1 -#define PPC_DEBUG_FEATURE_INSN_BP_MASK 0x2 -#define PPC_DEBUG_FEATURE_DATA_BP_RANGE 0x4 -#define PPC_DEBUG_FEATURE_DATA_BP_MASK 0x8 -#define PPC_DEBUG_FEATURE_DATA_BP_DAWR 0x10 - -2. PTRACE_SETHWDEBUG - -Sets a hardware breakpoint or watchpoint, according to the provided structure: - -struct ppc_hw_breakpoint { - uint32_t version; -#define PPC_BREAKPOINT_TRIGGER_EXECUTE 0x1 -#define PPC_BREAKPOINT_TRIGGER_READ 0x2 -#define PPC_BREAKPOINT_TRIGGER_WRITE 0x4 - uint32_t trigger_type; /* only some combinations allowed */ -#define PPC_BREAKPOINT_MODE_EXACT 0x0 -#define PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE 0x1 -#define PPC_BREAKPOINT_MODE_RANGE_EXCLUSIVE 0x2 -#define PPC_BREAKPOINT_MODE_MASK 0x3 - uint32_t addr_mode; /* address match mode */ - -#define PPC_BREAKPOINT_CONDITION_MODE 0x3 -#define PPC_BREAKPOINT_CONDITION_NONE 0x0 -#define PPC_BREAKPOINT_CONDITION_AND 0x1 -#define PPC_BREAKPOINT_CONDITION_EXACT 0x1 /* different name for the same thing as above */ -#define PPC_BREAKPOINT_CONDITION_OR 0x2 -#define PPC_BREAKPOINT_CONDITION_AND_OR 0x3 -#define PPC_BREAKPOINT_CONDITION_BE_ALL 0x00ff0000 /* byte enable bits */ -#define PPC_BREAKPOINT_CONDITION_BE(n) (1<<((n)+16)) - uint32_t condition_mode; /* break/watchpoint condition flags */ - - uint64_t addr; - uint64_t addr2; - uint64_t condition_value; -}; - -A request specifies one event, not necessarily just one register to be set. -For instance, if the request is for a watchpoint with a condition, both the -DAC and DVC registers will be set in the same request. - -With this GDB can ask for all kinds of hardware breakpoints and watchpoints -that the BookE supports. COMEFROM breakpoints available in server processors -are not contemplated, but that is out of the scope of this work. - -ptrace will return an integer (handle) uniquely identifying the breakpoint or -watchpoint just created. This integer will be used in the PTRACE_DELHWDEBUG -request to ask for its removal. Return -ENOSPC if the requested breakpoint -can't be allocated on the registers. - -Some examples of using the structure to: - -- set a breakpoint in the first breakpoint register - - p.version = PPC_DEBUG_CURRENT_VERSION; - p.trigger_type = PPC_BREAKPOINT_TRIGGER_EXECUTE; - p.addr_mode = PPC_BREAKPOINT_MODE_EXACT; - p.condition_mode = PPC_BREAKPOINT_CONDITION_NONE; - p.addr = (uint64_t) address; - p.addr2 = 0; - p.condition_value = 0; - -- set a watchpoint which triggers on reads in the second watchpoint register - - p.version = PPC_DEBUG_CURRENT_VERSION; - p.trigger_type = PPC_BREAKPOINT_TRIGGER_READ; - p.addr_mode = PPC_BREAKPOINT_MODE_EXACT; - p.condition_mode = PPC_BREAKPOINT_CONDITION_NONE; - p.addr = (uint64_t) address; - p.addr2 = 0; - p.condition_value = 0; - -- set a watchpoint which triggers only with a specific value - - p.version = PPC_DEBUG_CURRENT_VERSION; - p.trigger_type = PPC_BREAKPOINT_TRIGGER_READ; - p.addr_mode = PPC_BREAKPOINT_MODE_EXACT; - p.condition_mode = PPC_BREAKPOINT_CONDITION_AND | PPC_BREAKPOINT_CONDITION_BE_ALL; - p.addr = (uint64_t) address; - p.addr2 = 0; - p.condition_value = (uint64_t) condition; - -- set a ranged hardware breakpoint - - p.version = PPC_DEBUG_CURRENT_VERSION; - p.trigger_type = PPC_BREAKPOINT_TRIGGER_EXECUTE; - p.addr_mode = PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE; - p.condition_mode = PPC_BREAKPOINT_CONDITION_NONE; - p.addr = (uint64_t) begin_range; - p.addr2 = (uint64_t) end_range; - p.condition_value = 0; - -- set a watchpoint in server processors (BookS) - - p.version = 1; - p.trigger_type = PPC_BREAKPOINT_TRIGGER_RW; - p.addr_mode = PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE; - or - p.addr_mode = PPC_BREAKPOINT_MODE_EXACT; - - p.condition_mode = PPC_BREAKPOINT_CONDITION_NONE; - p.addr = (uint64_t) begin_range; - /* For PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE addr2 needs to be specified, where - * addr2 - addr <= 8 Bytes. - */ - p.addr2 = (uint64_t) end_range; - p.condition_value = 0; - -3. PTRACE_DELHWDEBUG - -Takes an integer which identifies an existing breakpoint or watchpoint -(i.e., the value returned from PTRACE_SETHWDEBUG), and deletes the -corresponding breakpoint or watchpoint.. |