From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59134) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aPufT-0004FY-Fp for qemu-devel@nongnu.org; Sun, 31 Jan 2016 11:16:04 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aPufS-0000sM-CL for qemu-devel@nongnu.org; Sun, 31 Jan 2016 11:16:03 -0500 From: Sergey Fedorov Date: Sun, 31 Jan 2016 19:15:47 +0300 Message-Id: <1454256948-10485-2-git-send-email-serge.fdrv@gmail.com> In-Reply-To: <1454256948-10485-1-git-send-email-serge.fdrv@gmail.com> References: <1454256948-10485-1-git-send-email-serge.fdrv@gmail.com> Subject: [Qemu-devel] [PATCH v3 1/2] cpu: Add callback to check architectural watchpoint match List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, qemu-arm@nongnu.org Cc: Peter Maydell , Peter Crosthwaite , Paolo Bonzini , Sergey Fedorov , =?UTF-8?q?Andreas=20F=C3=A4rber?= , Richard Henderson When QEMU watchpoint matches, that is not definitely an architectural watchpoint match yet. If it is a stop-before-access watchpoint then that is hardly possible to ignore it after throwing a TCG exception. A special callback is introduced to check for architectural watchpoint match before raising a TCG exception. Signed-off-by: Sergey Fedorov --- exec.c | 6 ++++++ include/qom/cpu.h | 4 ++++ qom/cpu.c | 9 +++++++++ 3 files changed, 19 insertions(+) diff --git a/exec.c b/exec.c index 9e076bc..14e7c76 100644 --- a/exec.c +++ b/exec.c @@ -2024,6 +2024,7 @@ static const MemoryRegionOps notdirty_mem_ops = { static void check_watchpoint(int offset, int len, MemTxAttrs attrs, int flags) { CPUState *cpu = current_cpu; + CPUClass *cc = CPU_GET_CLASS(cpu); CPUArchState *env = cpu->env_ptr; target_ulong pc, cs_base; target_ulong vaddr; @@ -2049,6 +2050,11 @@ static void check_watchpoint(int offset, int len, MemTxAttrs attrs, int flags) wp->hitaddr = vaddr; wp->hitattrs = attrs; if (!cpu->watchpoint_hit) { + if (wp->flags & BP_CPU && + !cc->debug_check_watchpoint(cpu, wp)) { + wp->flags &= ~BP_WATCHPOINT_HIT; + continue; + } cpu->watchpoint_hit = wp; tb_check_watchpoint(cpu); if (wp->flags & BP_STOP_BEFORE_ACCESS) { diff --git a/include/qom/cpu.h b/include/qom/cpu.h index 035179c..984bc8d 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -64,6 +64,7 @@ typedef uint64_t vaddr; #define CPU_GET_CLASS(obj) OBJECT_GET_CLASS(CPUClass, (obj), TYPE_CPU) typedef struct CPUState CPUState; +typedef struct CPUWatchpoint CPUWatchpoint; typedef void (*CPUUnassignedAccess)(CPUState *cpu, hwaddr addr, bool is_write, bool is_exec, int opaque, @@ -106,6 +107,8 @@ struct TranslationBlock; * a memory access with the specified memory transaction attributes. * @gdb_read_register: Callback for letting GDB read a register. * @gdb_write_register: Callback for letting GDB write a register. + * @debug_check_watchpoint: Callback: return true if the architectural + * watchpoint whose address has matched should really fire. * @debug_excp_handler: Callback for handling debug exceptions. * @write_elf64_note: Callback for writing a CPU-specific ELF note to a * 64-bit VM coredump. @@ -165,6 +168,7 @@ typedef struct CPUClass { int (*asidx_from_attrs)(CPUState *cpu, MemTxAttrs attrs); int (*gdb_read_register)(CPUState *cpu, uint8_t *buf, int reg); int (*gdb_write_register)(CPUState *cpu, uint8_t *buf, int reg); + bool (*debug_check_watchpoint)(CPUState *cpu, CPUWatchpoint *wp); void (*debug_excp_handler)(CPUState *cpu); int (*write_elf64_note)(WriteCoreDumpFunction f, CPUState *cpu, diff --git a/qom/cpu.c b/qom/cpu.c index 8f537a4..5a6a47e 100644 --- a/qom/cpu.c +++ b/qom/cpu.c @@ -188,6 +188,14 @@ static int cpu_common_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg) return 0; } +static bool cpu_common_debug_check_watchpoint(CPUState *cpu, CPUWatchpoint *wp) +{ + /* If no extra check is required, QEMU watchpoint match can be considered + * as an architectural match. + */ + return true; +} + bool target_words_bigendian(void); static bool cpu_common_virtio_is_big_endian(CPUState *cpu) { @@ -352,6 +360,7 @@ static void cpu_class_init(ObjectClass *klass, void *data) k->gdb_write_register = cpu_common_gdb_write_register; k->virtio_is_big_endian = cpu_common_virtio_is_big_endian; k->debug_excp_handler = cpu_common_noop; + k->debug_check_watchpoint = cpu_common_debug_check_watchpoint; k->cpu_exec_enter = cpu_common_noop; k->cpu_exec_exit = cpu_common_noop; k->cpu_exec_interrupt = cpu_common_exec_interrupt; -- 1.9.1