From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41601) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dzM4p-0001G2-UR for qemu-devel@nongnu.org; Tue, 03 Oct 2017 08:13:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dzM4l-0002ib-SV for qemu-devel@nongnu.org; Tue, 03 Oct 2017 08:13:31 -0400 Received: from mail-vk0-f43.google.com ([209.85.213.43]:55638) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1dzM4l-0002hH-Mw for qemu-devel@nongnu.org; Tue, 03 Oct 2017 08:13:27 -0400 Received: by mail-vk0-f43.google.com with SMTP id i1so4419235vke.12 for ; Tue, 03 Oct 2017 05:13:27 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <150642389679.3900.2803313967054050497.stgit@Misha-PC.lan02.inno> References: <150642384156.3900.3326424823772221077.stgit@Misha-PC.lan02.inno> <150642389679.3900.2803313967054050497.stgit@Misha-PC.lan02.inno> From: Ladi Prosek Date: Tue, 3 Oct 2017 14:13:26 +0200 Message-ID: Content-Type: text/plain; charset="UTF-8" Subject: Re: [Qemu-devel] [PATCH 09/43] windbg: handler of fs/gs register List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Mihail Abakumov Cc: qemu-devel , sw@weilnetz.de, Pavel Dovgalyuk , Roman Kagan , Paolo Bonzini , "Denis V. Lunev" On Tue, Sep 26, 2017 at 1:04 PM, Mihail Abakumov wrote: > Added handler of fs/gs register. It tries to find and check KPCR and version address. > > Signed-off-by: Mihail Abakumov > Signed-off-by: Pavel Dovgalyuk > Signed-off-by: Dmitriy Koltunov > --- > include/exec/windbgstub-utils.h | 5 +++ > windbgstub-utils.c | 63 ++++++++++++++++++++++++++++++++++++++- > 2 files changed, 66 insertions(+), 2 deletions(-) > > diff --git a/include/exec/windbgstub-utils.h b/include/exec/windbgstub-utils.h > index 90fb766839..f2402ebb34 100755 > --- a/include/exec/windbgstub-utils.h > +++ b/include/exec/windbgstub-utils.h > @@ -62,6 +62,11 @@ > _t; \ > }) > > +typedef struct InitedAddr { > + target_ulong addr; > + bool is_init; > +} InitedAddr; > + > bool windbg_on_load(void); > void windbg_on_exit(void); > > diff --git a/windbgstub-utils.c b/windbgstub-utils.c > index b5fb6db3f2..662096647e 100755 > --- a/windbgstub-utils.c > +++ b/windbgstub-utils.c > @@ -11,10 +11,69 @@ > > #include "exec/windbgstub-utils.h" > > +#ifdef TARGET_X86_64 > +# define OFFSET_SELF_PCR 0x18 > +# define OFFSET_VERS 0x108 > +#else > +# define OFFSET_SELF_PCR 0x1C > +# define OFFSET_VERS 0x34 > +#endif > + > +typedef struct KDData { > + InitedAddr KPCR; > + InitedAddr version; > +} KDData; > + > +static KDData *kd; > + > bool windbg_on_load(void) > { > - return false; > + CPUState *cpu = qemu_get_cpu(0); > + CPUArchState *env = cpu->env_ptr; > + > + if (!kd) { > + kd = g_new0(KDData, 1); > + } > + > + if (!kd->KPCR.is_init) { > + > + #ifdef TARGET_X86_64 > + kd->KPCR.addr = env->segs[R_GS].base; > + #else > + kd->KPCR.addr = env->segs[R_FS].base; > + #endif What if Windows is rebooted and FS/GS changes? Do you need to flip KPCR.is_init back to false on system reset? > + static target_ulong prev_KPCR; > + if (!kd->KPCR.addr || prev_KPCR == kd->KPCR.addr) { > + return false; > + } > + prev_KPCR = kd->KPCR.addr; > + > + if (kd->KPCR.addr != READ_VMEM(cpu, kd->KPCR.addr + OFFSET_SELF_PCR, > + target_ulong)) { > + return false; > + } > + > + kd->KPCR.is_init = true; > + } > + > + if (!kd->version.is_init && kd->KPCR.is_init) { > + kd->version.addr = READ_VMEM(cpu, kd->KPCR.addr + OFFSET_VERS, > + target_ulong); > + if (!kd->version.addr) { > + return false; > + } > + kd->version.is_init = true; > + } > + > + WINDBG_DEBUG("windbg_on_load: KPCR " FMT_ADDR, kd->KPCR.addr); > + WINDBG_DEBUG("windbg_on_load: version " FMT_ADDR, kd->version.addr); > + > + return true; > } > > void windbg_on_exit(void) > -{} > +{ > + g_free(kd); > + kd = NULL; > +} >