The branch main has been updated by bnovkov:
URL:
https://cgit.FreeBSD.org/src/commit/?id=b9951017bab396e24042e85632e2cc34ee0329ff
commit b9951017bab396e24042e85632e2cc34ee0329ff
Author: Bojan Novković <bnov...@freebsd.org>
AuthorDate: 2025-01-15 16:41:24 +0000
Commit: Bojan Novković <bnov...@freebsd.org>
CommitDate: 2025-01-22 12:58:34 +0000
amd64/fpu: Track supervisor state XSAVE components
The amd64/fpu.c xsave_* routines track supported XSAVE components and
features. However, they only track supported user state components, and
there is currently no way for a consumer to check whether the CPU
supports a supervisor state component. Fix this by saving the supported
supervisor state components, enumerated by CPUID function 0DH,
sub-function 1, in a separate mask.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D48466
---
sys/amd64/amd64/fpu.c | 38 ++++++++++++++++++++++++--------------
sys/x86/include/fpu.h | 5 +++--
2 files changed, 27 insertions(+), 16 deletions(-)
diff --git a/sys/amd64/amd64/fpu.c b/sys/amd64/amd64/fpu.c
index 591bd196ca7d..79d1722268b7 100644
--- a/sys/amd64/amd64/fpu.c
+++ b/sys/amd64/amd64/fpu.c
@@ -164,6 +164,7 @@ SYSCTL_INT(_hw, HW_FLOATINGPT, floatingpoint, CTLFLAG_RD,
int use_xsave; /* non-static for cpu_switch.S */
uint64_t xsave_mask; /* the same */
+static uint64_t xsave_mask_supervisor;
static uint64_t xsave_extensions;
static uma_zone_t fpu_save_area_zone;
static struct savefpu *fpu_initialstate;
@@ -324,6 +325,7 @@ fpuinit_bsp1(void)
ctx_switch_xsave[3] |= 0x10;
restore_wp(old_wp);
}
+ xsave_mask_supervisor = ((uint64_t)cp[3] << 32) | cp[2];
}
/*
@@ -421,7 +423,7 @@ fpuinitstate(void *arg __unused)
XSAVE_AREA_ALIGN - 1, 0);
fpu_initialstate = uma_zalloc(fpu_save_area_zone, M_WAITOK | M_ZERO);
if (use_xsave) {
- max_ext_n = flsl(xsave_mask);
+ max_ext_n = flsl(xsave_mask | xsave_mask_supervisor);
xsave_area_desc = malloc(max_ext_n * sizeof(struct
xsave_area_elm_descr), M_DEVBUF, M_WAITOK | M_ZERO);
}
@@ -1293,19 +1295,25 @@ fpu_save_area_reset(struct savefpu *fsa)
}
static __inline void
-xsave_extfeature_check(uint64_t feature)
+xsave_extfeature_check(uint64_t feature, bool supervisor)
{
+ uint64_t mask;
+ mask = supervisor ? xsave_mask_supervisor : xsave_mask;
KASSERT((feature & (feature - 1)) == 0,
("%s: invalid XFEATURE 0x%lx", __func__, feature));
- KASSERT(feature < flsl(xsave_mask),
- ("%s: unsupported XFEATURE 0x%lx", __func__, feature));
+ KASSERT(ilog2(feature) <= ilog2(mask),
+ ("%s: unsupported %s XFEATURE 0x%lx", __func__,
+ supervisor ? "supervisor" : "user", feature));
}
static __inline void
-xsave_extstate_bv_check(uint64_t xstate_bv)
+xsave_extstate_bv_check(uint64_t xstate_bv, bool supervisor)
{
- KASSERT(xstate_bv != 0 && ilog2(xstate_bv) < flsl(xsave_mask),
+ uint64_t mask;
+
+ mask = supervisor ? xsave_mask_supervisor : xsave_mask;
+ KASSERT(xstate_bv != 0 && ilog2(xstate_bv) <= ilog2(mask),
("%s: invalid XSTATE_BV 0x%lx", __func__, xstate_bv));
}
@@ -1317,11 +1325,13 @@ bool
xsave_extfeature_supported(uint64_t feature, bool supervisor)
{
int idx;
+ uint64_t mask;
KASSERT(use_xsave, ("%s: XSAVE not supported", __func__));
- xsave_extfeature_check(feature);
+ xsave_extfeature_check(feature, supervisor);
- if ((xsave_mask & feature) == 0)
+ mask = supervisor ? xsave_mask_supervisor : xsave_mask;
+ if ((mask & feature) == 0)
return (false);
idx = ilog2(feature);
return (((xsave_area_desc[idx].flags & CPUID_EXTSTATE_SUPERVISOR) != 0)
==
@@ -1345,15 +1355,15 @@ xsave_extension_supported(uint64_t extension)
*/
size_t
xsave_area_offset(uint64_t xstate_bv, uint64_t feature,
- bool compact)
+ bool compact, bool supervisor)
{
int i, idx;
size_t offs;
struct xsave_area_elm_descr *xep;
KASSERT(use_xsave, ("%s: XSAVE not supported", __func__));
- xsave_extstate_bv_check(xstate_bv);
- xsave_extfeature_check(feature);
+ xsave_extstate_bv_check(xstate_bv, supervisor);
+ xsave_extfeature_check(feature, supervisor);
idx = ilog2(feature);
if (!compact)
@@ -1376,16 +1386,16 @@ xsave_area_offset(uint64_t xstate_bv, uint64_t feature,
* 'xstate_bv' and extended region format ('compact').
*/
size_t
-xsave_area_size(uint64_t xstate_bv, bool compact)
+xsave_area_size(uint64_t xstate_bv, bool compact, bool supervisor)
{
int last_idx;
KASSERT(use_xsave, ("%s: XSAVE not supported", __func__));
- xsave_extstate_bv_check(xstate_bv);
+ xsave_extstate_bv_check(xstate_bv, supervisor);
last_idx = ilog2(xstate_bv);
- return (xsave_area_offset(xstate_bv, (uint64_t)1 << last_idx, compact) +
+ return (xsave_area_offset(xstate_bv, (uint64_t)1 << last_idx, compact,
supervisor) +
xsave_area_desc[last_idx].size);
}
diff --git a/sys/x86/include/fpu.h b/sys/x86/include/fpu.h
index 9d2e43f6386e..c94e058498f6 100644
--- a/sys/x86/include/fpu.h
+++ b/sys/x86/include/fpu.h
@@ -222,8 +222,9 @@ struct savefpu_ymm {
bool xsave_extfeature_supported(uint64_t feature, bool supervisor);
bool xsave_extension_supported(uint64_t extension);
size_t xsave_area_hdr_offset(void);
-size_t xsave_area_offset(uint64_t xstate_bv, uint64_t feature, bool compact);
-size_t xsave_area_size(uint64_t xstate_bv, bool compact);
+size_t xsave_area_offset(uint64_t xstate_bv, uint64_t feature, bool compact,
+ bool supervisor);
+size_t xsave_area_size(uint64_t xstate_bv, bool compact, bool supervisor);
#endif
#endif /* !_X86_FPU_H_ */
