From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37026) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fxpq5-0007Rr-NI for qemu-devel@nongnu.org; Thu, 06 Sep 2018 04:40:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fxpq2-000361-7y for qemu-devel@nongnu.org; Thu, 06 Sep 2018 04:40:33 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:40734 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fxppy-0002wt-Ov for qemu-devel@nongnu.org; Thu, 06 Sep 2018 04:40:29 -0400 Date: Thu, 6 Sep 2018 10:40:14 +0200 From: Igor Mammedov Message-ID: <20180906104014.3a09e9d4@redhat.com> In-Reply-To: References: <20180831172424.12029-1-marcandre.lureau@redhat.com> <20180831172424.12029-7-marcandre.lureau@redhat.com> <20180904084648.680c564b@redhat.com> <20180906095802.7dffbf1b@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v10 6/6] tpm: add ACPI memory clear interface List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?TWFyYy1BbmRyw6k=?= Lureau Cc: Eduardo Habkost , Stefan Berger , "Michael S. Tsirkin" , QEMU , Paolo Bonzini , Richard Henderson , "Dr. David Alan Gilbert" On Thu, 6 Sep 2018 12:01:40 +0400 Marc-Andr=C3=A9 Lureau wrote: > Hi >=20 > On Thu, Sep 6, 2018 at 11:58 AM Igor Mammedov wrote: > > > > On Thu, 6 Sep 2018 07:50:09 +0400 > > Marc-Andr=C3=A9 Lureau wrote: > > =20 > > > Hi > > > > > > On Tue, Sep 4, 2018 at 10:47 AM Igor Mammedov w= rote: =20 > > > > > > > > On Fri, 31 Aug 2018 19:24:24 +0200 > > > > Marc-Andr=C3=A9 Lureau wrote: > > > > =20 > > > > > This allows to pass the last failing test from the Windows HLK TP= M 2.0 > > > > > TCG PPI 1.3 tests. > > > > > > > > > > The interface is described in the "TCG Platform Reset Attack > > > > > Mitigation Specification", chapter 6 "ACPI _DSM Function". Accord= ing > > > > > to Laszlo, it's not so easy to implement in OVMF, he suggested to= do > > > > > it in qemu instead. > > > > > > > > > > Signed-off-by: Marc-Andr=C3=A9 Lureau > > > > > --- > > > > > hw/tpm/tpm_ppi.h | 2 ++ > > > > > hw/i386/acpi-build.c | 46 ++++++++++++++++++++++++++++++++++++++= ++++++ > > > > > hw/tpm/tpm_crb.c | 1 + > > > > > hw/tpm/tpm_ppi.c | 23 ++++++++++++++++++++++ > > > > > hw/tpm/tpm_tis.c | 1 + > > > > > docs/specs/tpm.txt | 2 ++ > > > > > hw/tpm/trace-events | 3 +++ > > > > > 7 files changed, 78 insertions(+) > > > > > > > > > > diff --git a/hw/tpm/tpm_ppi.h b/hw/tpm/tpm_ppi.h > > > > > index f6458bf87e..3239751e9f 100644 > > > > > --- a/hw/tpm/tpm_ppi.h > > > > > +++ b/hw/tpm/tpm_ppi.h > > > > > @@ -23,4 +23,6 @@ typedef struct TPMPPI { > > > > > bool tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m, > > > > > hwaddr addr, Object *obj, Error **errp); > > > > > > > > > > +void tpm_ppi_reset(TPMPPI *tpmppi); > > > > > + > > > > > #endif /* TPM_TPM_PPI_H */ > > > > > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c > > > > > index c5e9a6e11d..2ab3e8fae7 100644 > > > > > --- a/hw/i386/acpi-build.c > > > > > +++ b/hw/i386/acpi-build.c > > > > > @@ -1824,6 +1824,13 @@ build_tpm_ppi(TPMIf *tpm, Aml *dev) > > > > > pprq =3D aml_name("PPRQ"); > > > > > pprm =3D aml_name("PPRM"); > > > > > > > > > > + aml_append(dev, > > > > > + aml_operation_region("TPP3", AML_SYSTEM_MEMORY, > > > > > + aml_int(TPM_PPI_ADDR_BASE + = 0x15a), > > > > > + 0x1)); > > > > > + field =3D aml_field("TPP3", AML_BYTE_ACC, AML_NOLOCK, AML_PR= ESERVE); > > > > > + aml_append(field, aml_named_field("MOVV", 8)); > > > > > + aml_append(dev, field); > > > > > /* > > > > > * DerefOf in Windows is broken with SYSTEM_MEMORY. Use a d= ynamic > > > > > * operation region inside of a method for getting FUNC[op]. > > > > > @@ -2166,7 +2173,46 @@ build_tpm_ppi(TPMIf *tpm, Aml *dev) > > > > > aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)= )); > > > > > } > > > > > aml_append(method, ifctx); > > > > > + > > > > > + ifctx =3D aml_if( > > > > > + aml_equal(uuid, > > > > > + aml_touuid("376054ED-CC13-4675-901C-4756D7= F2D45D"))); > > > > > + { > > > > > + /* standard DSM query function */ > > > > > + ifctx2 =3D aml_if(aml_equal(function, zero)); > > > > > + { > > > > > + uint8_t byte_list[1] =3D { 0x03 }; > > > > > + aml_append(ifctx2, aml_return(aml_buffer(1, byte= _list))); > > > > > + } > > > > > + aml_append(ifctx, ifctx2); > > > > > + > > > > > + /* > > > > > + * TCG Platform Reset Attack Mitigation Specificatio= n 1.0 Ch.6 > > > > > + * > > > > > + * Arg 2 (Integer): Function Index =3D 1 > > > > > + * Arg 3 (Package): Arguments =3D Package: Type: Int= eger > > > > > + * Operation Value of the Request > > > > > + * Returns: Type: Integer > > > > > + * 0: Success > > > > > + * 1: General Failure > > > > > + */ > > > > > + ifctx2 =3D aml_if(aml_equal(function, one)); > > > > > + { > > > > > + aml_append(ifctx2, > > > > > + aml_store(aml_derefof(aml_index(argum= ents, zero)), > > > > > + op)); > > > > > + { > > > > > + aml_append(ifctx2, aml_store(op, aml_name("M= OVV"))); > > > > > + > > > > > + /* 0: success */ > > > > > + aml_append(ifctx2, aml_return(zero)); > > > > > + } > > > > > + } > > > > > + aml_append(ifctx, ifctx2); > > > > > + } > > > > > + aml_append(method, ifctx); > > > > > } > > > > > + > > > > > aml_append(dev, method); > > > > > } > > > > > > > > > > diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c > > > > > index b243222fd6..48f6a716ad 100644 > > > > > --- a/hw/tpm/tpm_crb.c > > > > > +++ b/hw/tpm/tpm_crb.c > > > > > @@ -233,6 +233,7 @@ static void tpm_crb_reset(void *dev) > > > > > { > > > > > CRBState *s =3D CRB(dev); > > > > > > > > > > + tpm_ppi_reset(&s->ppi); > > > > > tpm_backend_reset(s->tpmbe); > > > > > > > > > > memset(s->regs, 0, sizeof(s->regs)); > > > > > diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c > > > > > index 8b46b9dd4b..ce43bc5729 100644 > > > > > --- a/hw/tpm/tpm_ppi.c > > > > > +++ b/hw/tpm/tpm_ppi.c > > > > > @@ -16,8 +16,30 @@ > > > > > #include "qapi/error.h" > > > > > #include "cpu.h" > > > > > #include "sysemu/memory_mapping.h" > > > > > +#include "sysemu/reset.h" > > > > > #include "migration/vmstate.h" > > > > > #include "tpm_ppi.h" > > > > > +#include "trace.h" > > > > > + > > > > > +void tpm_ppi_reset(TPMPPI *tpmppi) > > > > > +{ =20 > > > > > > > > =20 > > > > > + char *ptr =3D memory_region_get_ram_ptr(&tpmppi->ram); =20 > > > > nvdimm seems to use cpu_physical_memory_read() to access guest > > > > accessible memory, so question is what's difference? =20 > > > > > > cpu_physical_memory_read() is higher level, doing dispatch on address > > > and length checks. > > > > > > This is a bit unnecessary, as ppi->buf could be accessed directly. =20 > > [...] =20 > > > > > + memset(block->host_addr, 0, > > > > > + block->target_end - block->target_start); > > > > > + } =20 > > my concern here is that if we directly touch guest memory here > > we might get in trouble on migration without dirtying modified > > ranges =20 >=20 > It is a read-only of one byte. > by the time the reset handler is called, the memory must have been > already migrated. what about memset(), it looks like we are writing to guest memory. Shouldn't we dirty zeroed out blocks? > > > > PS: > > feel free it ignore since I don't have a clue what I'm talking about :) > > =20 > > > > > + guest_phys_blocks_free(&guest_phys_blocks); > > > > > + } > > > > > +} > > > > > > > > > > bool tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m, > > > > > hwaddr addr, Object *obj, Error **errp) > > > > > @@ -27,5 +49,6 @@ bool tpm_ppi_init(TPMPPI *tpmppi, struct Memory= Region *m, > > > > > vmstate_register_ram(&tpmppi->ram, DEVICE(obj)); > > > > > > > > > > memory_region_add_subregion(m, addr, &tpmppi->ram); > > > > > + > > > > > return true; > > > > > } > > > > > diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c > > > > > index 70432ffe8b..d9bfa956cc 100644 > > > > > --- a/hw/tpm/tpm_tis.c > > > > > +++ b/hw/tpm/tpm_tis.c > > > > > @@ -868,6 +868,7 @@ static void tpm_tis_reset(DeviceState *dev) > > > > > s->be_buffer_size =3D MIN(tpm_backend_get_buffer_size(s->be_= driver), > > > > > TPM_TIS_BUFFER_MAX); > > > > > > > > > > + tpm_ppi_reset(&s->ppi); > > > > > tpm_backend_reset(s->be_driver); > > > > > > > > > > s->active_locty =3D TPM_TIS_NO_LOCALITY; > > > > > diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt > > > > > index 332c2ae597..ce9bda3c89 100644 > > > > > --- a/docs/specs/tpm.txt > > > > > +++ b/docs/specs/tpm.txt > > > > > @@ -121,6 +121,8 @@ layout: > > > > > +----------+--------+--------+---------------------------------= ----------+ > > > > > | next_step| 0x1 | 0x159 | Operation to execute after reboo= t by | > > > > > | | | | firmware. Used by firmware. = | > > > > > + +----------+--------+--------+---------------------------------= ----------+ > > > > > + | movv | 0x1 | 0x15a | Memory overwrite variable = | > > > > > +----------+--------+--------+---------------------------------= ----------+ > > > > > > > > > > The following values are supported for the 'func' field. They= correspond > > > > > diff --git a/hw/tpm/trace-events b/hw/tpm/trace-events > > > > > index 25bee0cecf..920d32ad55 100644 > > > > > --- a/hw/tpm/trace-events > > > > > +++ b/hw/tpm/trace-events > > > > > @@ -51,3 +51,6 @@ tpm_tis_mmio_write_init_abort(void) "Initiating= abort" > > > > > tpm_tis_mmio_write_lowering_irq(void) "Lowering IRQ" > > > > > tpm_tis_mmio_write_data2send(uint32_t value, unsigned size) "Dat= a to send to TPM: 0x%08x (size=3D%d)" > > > > > tpm_tis_pre_save(uint8_t locty, uint32_t rw_offset) "locty: %d, = rw_offset =3D %u" > > > > > + > > > > > +# hw/tpm/tpm_ppi.c > > > > > +tpm_ppi_memset(uint8_t *ptr, size_t size) "memset: %p %zu" =20 > > > > > > > > =20 > > > > > > =20 > > =20 >=20 >=20