From: "Chang S. Bae" <chang.seok.bae@intel.com>
To: bp@suse.de, luto@kernel.org, tglx@linutronix.de,
mingo@kernel.org, x86@kernel.org
Cc: len.brown@intel.com, dave.hansen@intel.com, jing2.liu@intel.com,
ravi.v.shankar@intel.com, linux-kernel@vger.kernel.org,
chang.seok.bae@intel.com, kvm@vger.kernel.org
Subject: [PATCH v5 01/28] x86/fpu/xstate: Modify the initialization helper to handle both static and dynamic buffers
Date: Sun, 23 May 2021 12:32:32 -0700 [thread overview]
Message-ID: <20210523193259.26200-2-chang.seok.bae@intel.com> (raw)
In-Reply-To: <20210523193259.26200-1-chang.seok.bae@intel.com>
Have the function initializing the xstate buffer take a struct fpu *
pointer in preparation for dynamic state buffer support.
init_fpstate is a special case, which is indicated by a null pointer
parameter to fpstate_init().
Also, fpstate_init_xstate() now accepts the state component bitmap to
configure XCOMP_BV for the compacted format.
No functional change.
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Reviewed-by: Len Brown <len.brown@intel.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: kvm@vger.kernel.org
---
Changes from v4:
* Added a proper function description. (Borislav Petkov)
* Added the likely() statement as a null pointer is a special case.
Changes from v3:
* Updated the changelog. (Borislav Petkov)
* Updated the function comment to use kernel-doc style. (Borislav Petkov)
Changes from v2:
* Updated the changelog with task->fpu removed. (Borislav Petkov)
---
arch/x86/include/asm/fpu/internal.h | 6 +++---
arch/x86/kernel/fpu/core.c | 23 ++++++++++++++++++++---
arch/x86/kernel/fpu/init.c | 2 +-
arch/x86/kernel/fpu/regset.c | 2 +-
arch/x86/kernel/fpu/xstate.c | 3 +--
arch/x86/kvm/x86.c | 2 +-
6 files changed, 27 insertions(+), 11 deletions(-)
diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index 8d33ad80704f..d81d8c407dc0 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -80,20 +80,20 @@ static __always_inline __pure bool use_fxsr(void)
extern union fpregs_state init_fpstate;
-extern void fpstate_init(union fpregs_state *state);
+extern void fpstate_init(struct fpu *fpu);
#ifdef CONFIG_MATH_EMULATION
extern void fpstate_init_soft(struct swregs_state *soft);
#else
static inline void fpstate_init_soft(struct swregs_state *soft) {}
#endif
-static inline void fpstate_init_xstate(struct xregs_state *xsave)
+static inline void fpstate_init_xstate(struct xregs_state *xsave, u64 xcomp_mask)
{
/*
* XRSTORS requires these bits set in xcomp_bv, or it will
* trigger #GP:
*/
- xsave->header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | xfeatures_mask_all;
+ xsave->header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT | xcomp_mask;
}
static inline void fpstate_init_fxstate(struct fxregs_state *fx)
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 571220ac8bea..52f886477b07 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -192,8 +192,25 @@ static inline void fpstate_init_fstate(struct fregs_state *fp)
fp->fos = 0xffff0000u;
}
-void fpstate_init(union fpregs_state *state)
+/**
+ *
+ * fpstate_init() - initialize the xstate buffer
+ *
+ * If @fpu is NULL, initialize init_fpstate.
+ *
+ * @fpu: A struct fpu * pointer
+ *
+ * Returns nothing.
+ */
+void fpstate_init(struct fpu *fpu)
{
+ union fpregs_state *state;
+
+ if (likely(fpu))
+ state = &fpu->state;
+ else
+ state = &init_fpstate;
+
if (!static_cpu_has(X86_FEATURE_FPU)) {
fpstate_init_soft(&state->soft);
return;
@@ -202,7 +219,7 @@ void fpstate_init(union fpregs_state *state)
memset(state, 0, fpu_kernel_xstate_size);
if (static_cpu_has(X86_FEATURE_XSAVES))
- fpstate_init_xstate(&state->xsave);
+ fpstate_init_xstate(&state->xsave, xfeatures_mask_all);
if (static_cpu_has(X86_FEATURE_FXSR))
fpstate_init_fxstate(&state->fxsave);
else
@@ -262,7 +279,7 @@ static void fpu__initialize(struct fpu *fpu)
WARN_ON_FPU(fpu != ¤t->thread.fpu);
set_thread_flag(TIF_NEED_FPU_LOAD);
- fpstate_init(&fpu->state);
+ fpstate_init(fpu);
trace_x86_fpu_init_state(fpu);
}
diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c
index 701f196d7c68..74e03e3bc20f 100644
--- a/arch/x86/kernel/fpu/init.c
+++ b/arch/x86/kernel/fpu/init.c
@@ -124,7 +124,7 @@ static void __init fpu__init_system_generic(void)
* Set up the legacy init FPU context. (xstate init might overwrite this
* with a more modern format, if the CPU supports it.)
*/
- fpstate_init(&init_fpstate);
+ fpstate_init(NULL);
fpu__init_system_mxcsr();
}
diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c
index c413756ba89f..4c4d9059ff36 100644
--- a/arch/x86/kernel/fpu/regset.c
+++ b/arch/x86/kernel/fpu/regset.c
@@ -144,7 +144,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
* In case of failure, mark all states as init:
*/
if (ret)
- fpstate_init(&fpu->state);
+ fpstate_init(fpu);
return ret;
}
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index a85c64000218..767ad6b008c2 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -457,8 +457,7 @@ static void __init setup_init_fpu_buf(void)
print_xstate_features();
if (boot_cpu_has(X86_FEATURE_XSAVES))
- init_fpstate.xsave.header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT |
- xfeatures_mask_all;
+ fpstate_init_xstate(&init_fpstate.xsave, xfeatures_mask_all);
/*
* Init all the features state with header.xfeatures being 0x0
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bbc4e04e67ad..9af0a3c52b62 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10248,7 +10248,7 @@ static void fx_init(struct kvm_vcpu *vcpu)
if (!vcpu->arch.guest_fpu)
return;
- fpstate_init(&vcpu->arch.guest_fpu->state);
+ fpstate_init(vcpu->arch.guest_fpu);
if (boot_cpu_has(X86_FEATURE_XSAVES))
vcpu->arch.guest_fpu->state.xsave.header.xcomp_bv =
host_xcr0 | XSTATE_COMPACTION_ENABLED;
--
2.17.1
next parent reply other threads:[~2021-05-23 19:38 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210523193259.26200-1-chang.seok.bae@intel.com>
2021-05-23 19:32 ` Chang S. Bae [this message]
2021-05-23 19:32 ` [PATCH v5 03/28] x86/fpu/xstate: Modify address finders to handle both static and dynamic buffers Chang S. Bae
2021-05-23 19:32 ` [PATCH v5 04/28] x86/fpu/xstate: Modify the context restore helper " Chang S. Bae
2021-05-23 19:32 ` [PATCH v5 06/28] x86/fpu/xstate: Add new variables to indicate dynamic xstate buffer size Chang S. Bae
2021-05-23 19:32 ` [PATCH v5 08/28] x86/fpu/xstate: Convert the struct fpu 'state' field to a pointer Chang S. Bae
2021-05-23 19:32 ` [PATCH v5 11/28] x86/fpu/xstate: Update the xstate save function to support dynamic states Chang S. Bae
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210523193259.26200-2-chang.seok.bae@intel.com \
--to=chang.seok.bae@intel.com \
--cc=bp@suse.de \
--cc=dave.hansen@intel.com \
--cc=jing2.liu@intel.com \
--cc=kvm@vger.kernel.org \
--cc=len.brown@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@kernel.org \
--cc=ravi.v.shankar@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).