From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Michael Neuling To: benh@kernel.crashing.org MIME-Version: 1.0 Subject: [PATCH] powerpc/ptrace: Add DAWR debug feature info for userspace Date: Fri, 22 Mar 2013 17:12:33 +1100 Message-ID: <15228.1363932753@ale.ozlabs.ibm.com> Cc: Linux PPC dev , Edjunior Barbosa Machado , David Gibson List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This adds new debug feature information so that the DAWR can be identified by userspace tools like GDB. Unfortunately the DAWR doesn't sit nicely into the current description that ptrace provides to userspace via struct ppc_debug_info. It doesn't allow for specifying that only some ranges are possible or even the end alignment constraints (DAWR only allows 512 byte wide ranges which can't cross a 512 byte boundary). After talking to Edjunior Machado (GDB ppc developer), it was decided this was the best approach. Just mark it as debug feature DAWR and tools like GDB can internally decide the constraints. Signed-off-by: Michael Neuling diff --git a/Documentation/powerpc/ptrace.txt b/Documentation/powerpc/ptrace.txt index f2a7a39..99c5ce8 100644 --- a/Documentation/powerpc/ptrace.txt +++ b/Documentation/powerpc/ptrace.txt @@ -40,6 +40,7 @@ features will have bits indicating whether there is support for: #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 diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h index 66b9ca4..77d2ed3 100644 --- a/arch/powerpc/include/uapi/asm/ptrace.h +++ b/arch/powerpc/include/uapi/asm/ptrace.h @@ -211,6 +211,7 @@ struct ppc_debug_info { #define PPC_DEBUG_FEATURE_INSN_BP_MASK 0x0000000000000002 #define PPC_DEBUG_FEATURE_DATA_BP_RANGE 0x0000000000000004 #define PPC_DEBUG_FEATURE_DATA_BP_MASK 0x0000000000000008 +#define PPC_DEBUG_FEATURE_DATA_BP_DAWR 0x0000000000000010 #ifndef __ASSEMBLY__ diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index f9b30c6..8240c1a 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -1637,6 +1637,8 @@ long arch_ptrace(struct task_struct *child, long request, dbginfo.sizeof_condition = 0; #ifdef CONFIG_HAVE_HW_BREAKPOINT dbginfo.features = PPC_DEBUG_FEATURE_DATA_BP_RANGE; + if (cpu_has_feature(CPU_FTR_DAWR)) + dbginfo.features |= PPC_DEBUG_FEATURE_DATA_BP_DAWR; #else dbginfo.features = 0; #endif /* CONFIG_HAVE_HW_BREAKPOINT */