Commit ab4752ec authored by Jon Doron's avatar Jon Doron Committed by Alex Bennée
Browse files

gdbstub: Implement qemu physical memory mode 



Add a new query/set which changes the memory GDB sees to physical memory
only.

gdb> maint packet qqemu.PhyMemMode
will reply the current phy_mem_mode state (1 for enabled, 0 for disabled)
gdb> maint packet Qqemu.PhyMemMode:1
Will make GDB read/write only to physical memory, set to 0 to disable

Signed-off-by: default avatarJon Doron <arilou@gmail.com>
Message-Id: <20190529064148.19856-21-arilou@gmail.com>
Signed-off-by: default avatarAlex Bennée <alex.bennee@linaro.org>
parent 3f1cbac7

gdbstub.c

+60 −2
Original line number Diff line number Diff line
@@ -50,11 +50,27 @@ 
#define GDB_ATTACHED "1"

#endif



#ifndef CONFIG_USER_ONLY

static int phy_memory_mode;

#endif



static inline int target_memory_rw_debug(CPUState *cpu, target_ulong addr,

                                         uint8_t *buf, int len, bool is_write)

{

    CPUClass *cc = CPU_GET_CLASS(cpu);

    CPUClass *cc;



#ifndef CONFIG_USER_ONLY

    if (phy_memory_mode) {

        if (is_write) {

            cpu_physical_memory_write(addr, buf, len);

        } else {

            cpu_physical_memory_read(addr, buf, len);

        }

        return 0;

    }

#endif



    cc = CPU_GET_CLASS(cpu);

    if (cc->memory_rw_debug) {

        return cc->memory_rw_debug(cpu, addr, buf, len, is_write);

    }
@@ -2136,9 +2152,37 @@ static void handle_query_attached(GdbCmdContext *gdb_ctx, void *user_ctx) 


static void handle_query_qemu_supported(GdbCmdContext *gdb_ctx, void *user_ctx)

{

    put_packet(gdb_ctx->s, "sstepbits;sstep");

    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "sstepbits;sstep");

#ifndef CONFIG_USER_ONLY

    pstrcat(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), ";PhyMemMode");

#endif

    put_packet(gdb_ctx->s, gdb_ctx->str_buf);

}



#ifndef CONFIG_USER_ONLY

static void handle_query_qemu_phy_mem_mode(GdbCmdContext *gdb_ctx,

                                           void *user_ctx)

{

    snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "%d", phy_memory_mode);

    put_packet(gdb_ctx->s, gdb_ctx->str_buf);

}



static void handle_set_qemu_phy_mem_mode(GdbCmdContext *gdb_ctx, void *user_ctx)

{

    if (!gdb_ctx->num_params) {

        put_packet(gdb_ctx->s, "E22");

        return;

    }



    if (!gdb_ctx->params[0].val_ul) {

        phy_memory_mode = 0;

    } else {

        phy_memory_mode = 1;

    }

    put_packet(gdb_ctx->s, "OK");

}

#endif



static GdbCmdParseEntry gdb_gen_query_set_common_table[] = {

    /* Order is important if has same prefix */

    {
@@ -2219,6 +2263,12 @@ static GdbCmdParseEntry gdb_gen_query_table[] = { 
        .handler = handle_query_qemu_supported,

        .cmd = "qemu.Supported",

    },

#ifndef CONFIG_USER_ONLY

    {

        .handler = handle_query_qemu_phy_mem_mode,

        .cmd = "qemu.PhyMemMode",

    },

#endif

};



static GdbCmdParseEntry gdb_gen_set_table[] = {
@@ -2229,6 +2279,14 @@ static GdbCmdParseEntry gdb_gen_set_table[] = { 
        .cmd_startswith = 1,

        .schema = "l0"

    },

#ifndef CONFIG_USER_ONLY

    {

        .handler = handle_set_qemu_phy_mem_mode,

        .cmd = "qemu.PhyMemMode:",

        .cmd_startswith = 1,

        .schema = "l0"

    },

#endif

};



static void handle_gen_query(GdbCmdContext *gdb_ctx, void *user_ctx)