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| author | Florian Weimer <fweimer@redhat.com> | 2025-03-28 09:26:59 +0100 |
|---|---|---|
| committer | Florian Weimer <fweimer@redhat.com> | 2025-03-29 10:19:51 +0100 |
| commit | df22af58f66e6815c054b1c56249356c2994935a (patch) | |
| tree | c12993fe79490ca020e01502ca0ecd0175468460 | |
| parent | 8fc492bb4234edc1a5e8c3b7f76ba345ea7109ec (diff) | |
| download | glibc-release/2.40/master.zip glibc-release/2.40/master.tar.gz glibc-release/2.40/master.tar.bz2 | |
x86: Use separate variable for TLSDESC XSAVE/XSAVEC state size (bug 32810)release/2.40/master
Previously, the initialization code reused the xsave_state_full_size
member of struct cpu_features for the TLSDESC state size. However,
the tunable processing code assumes that this member has the
original XSAVE (non-compact) state size, so that it can use its
value if XSAVEC is disabled via tunable.
This change uses a separate variable and not a struct member because
the value is only needed in ld.so and the static libc, but not in
libc.so. As a result, struct cpu_features layout does not change,
helping a future backport of this change.
Fixes commit 9b7091415af47082664717210ac49d51551456ab ("x86-64:
Update _dl_tlsdesc_dynamic to preserve AMX registers").
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 145097dff170507fe73190e8e41194f5b5f7e6bf)
| -rw-r--r-- | NEWS | 1 | ||||
| -rw-r--r-- | sysdeps/x86/Makefile | 19 | ||||
| -rw-r--r-- | sysdeps/x86/cpu-features.c | 11 | ||||
| -rw-r--r-- | sysdeps/x86/cpu-tunables.c | 2 | ||||
| -rw-r--r-- | sysdeps/x86/dl-diagnostics-cpu.c | 2 | ||||
| -rw-r--r-- | sysdeps/x86/include/cpu-features.h | 9 | ||||
| -rw-r--r-- | sysdeps/x86/tst-gnu2-tls2-x86-noxsave.c | 1 | ||||
| -rw-r--r-- | sysdeps/x86/tst-gnu2-tls2-x86-noxsavec.c | 1 | ||||
| -rw-r--r-- | sysdeps/x86/tst-gnu2-tls2-x86-noxsavexsavec.c | 1 | ||||
| -rw-r--r-- | sysdeps/x86_64/dl-tlsdesc-dynamic.h | 2 |
10 files changed, 41 insertions, 8 deletions
@@ -22,6 +22,7 @@ The following bugs are resolved with this release: [32231] elf: Change ldconfig auxcache magic number [32245] glibc -Wstringop-overflow= build failure on hppa [32470] x86: Avoid integer truncation with large cache sizes + [32810] Crash on x86-64 if XSAVEC disable via tunable Version 2.40 diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile index 5311b59..8819fba 100644 --- a/sysdeps/x86/Makefile +++ b/sysdeps/x86/Makefile @@ -21,6 +21,9 @@ tests += \ tst-cpu-features-supports-static \ tst-get-cpu-features \ tst-get-cpu-features-static \ + tst-gnu2-tls2-x86-noxsave \ + tst-gnu2-tls2-x86-noxsavec \ + tst-gnu2-tls2-x86-noxsavexsavec \ tst-hwcap-tunables \ # tests tests-static += \ @@ -91,6 +94,22 @@ CFLAGS-tst-gnu2-tls2.c += -msse CFLAGS-tst-gnu2-tls2mod0.c += -msse2 -mtune=haswell CFLAGS-tst-gnu2-tls2mod1.c += -msse2 -mtune=haswell CFLAGS-tst-gnu2-tls2mod2.c += -msse2 -mtune=haswell + +LDFLAGS-tst-gnu2-tls2-x86-noxsave += -Wl,-z,lazy +LDFLAGS-tst-gnu2-tls2-x86-noxsavec += -Wl,-z,lazy +LDFLAGS-tst-gnu2-tls2-x86-noxsavexsavec += -Wl,-z,lazy + +# Test for bug 32810: incorrect XSAVE state size if XSAVEC is disabled +# via tunable. +tst-gnu2-tls2-x86-noxsave-ENV = GLIBC_TUNABLES=glibc.cpu.hwcaps=-XSAVE +tst-gnu2-tls2-x86-noxsavec-ENV = GLIBC_TUNABLES=glibc.cpu.hwcaps=-XSAVEC +tst-gnu2-tls2-x86-noxsavexsavec-ENV = GLIBC_TUNABLES=glibc.cpu.hwcaps=-XSAVE,-XSAVEC +$(objpfx)tst-gnu2-tls2-x86-noxsave.out \ +$(objpfx)tst-gnu2-tls2-x86-noxsavec.out \ +$(objpfx)tst-gnu2-tls2-x86-noxsavexsavec.out: \ + $(objpfx)tst-gnu2-tls2mod0.so \ + $(objpfx)tst-gnu2-tls2mod1.so \ + $(objpfx)tst-gnu2-tls2mod2.so endif ifeq ($(subdir),math) diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c index b5b264d..ec27337 100644 --- a/sysdeps/x86/cpu-features.c +++ b/sysdeps/x86/cpu-features.c @@ -84,6 +84,8 @@ extern void TUNABLE_CALLBACK (set_x86_shstk) (tunable_val_t *) # include <dl-cet.h> #endif +unsigned long int _dl_x86_features_tlsdesc_state_size; + static void update_active (struct cpu_features *cpu_features) { @@ -318,6 +320,7 @@ update_active (struct cpu_features *cpu_features) = xsave_state_full_size; cpu_features->xsave_state_full_size = xsave_state_full_size; + _dl_x86_features_tlsdesc_state_size = xsave_state_full_size; /* Check if XSAVEC is available. */ if (CPU_FEATURES_CPU_P (cpu_features, XSAVEC)) @@ -406,11 +409,9 @@ update_active (struct cpu_features *cpu_features) = ALIGN_UP ((amx_size + TLSDESC_CALL_REGISTER_SAVE_AREA), 64); - /* Set xsave_state_full_size to the compact AMX - state size for XSAVEC. NB: xsave_state_full_size - is only used in _dl_tlsdesc_dynamic_xsave and - _dl_tlsdesc_dynamic_xsavec. */ - cpu_features->xsave_state_full_size = amx_size; + /* Set TLSDESC state size to the compact AMX + state size for XSAVEC. */ + _dl_x86_features_tlsdesc_state_size = amx_size; #endif cpu_features->xsave_state_size = ALIGN_UP (size + TLSDESC_CALL_REGISTER_SAVE_AREA, diff --git a/sysdeps/x86/cpu-tunables.c b/sysdeps/x86/cpu-tunables.c index ccc6b64..a0b31d8 100644 --- a/sysdeps/x86/cpu-tunables.c +++ b/sysdeps/x86/cpu-tunables.c @@ -164,6 +164,8 @@ TUNABLE_CALLBACK (set_hwcaps) (tunable_val_t *valp) /* Update xsave_state_size to XSAVE state size. */ cpu_features->xsave_state_size = cpu_features->xsave_state_full_size; + _dl_x86_features_tlsdesc_state_size + = cpu_features->xsave_state_full_size; CPU_FEATURE_UNSET (cpu_features, XSAVEC); } } diff --git a/sysdeps/x86/dl-diagnostics-cpu.c b/sysdeps/x86/dl-diagnostics-cpu.c index 49eeb5f..41100a9 100644 --- a/sysdeps/x86/dl-diagnostics-cpu.c +++ b/sysdeps/x86/dl-diagnostics-cpu.c @@ -89,6 +89,8 @@ _dl_diagnostics_cpu (void) cpu_features->xsave_state_size); print_cpu_features_value ("xsave_state_full_size", cpu_features->xsave_state_full_size); + print_cpu_features_value ("tlsdesc_state_full_size", + _dl_x86_features_tlsdesc_state_size); print_cpu_features_value ("data_cache_size", cpu_features->data_cache_size); print_cpu_features_value ("shared_cache_size", cpu_features->shared_cache_size); diff --git a/sysdeps/x86/include/cpu-features.h b/sysdeps/x86/include/cpu-features.h index aaae44f..03c7138 100644 --- a/sysdeps/x86/include/cpu-features.h +++ b/sysdeps/x86/include/cpu-features.h @@ -934,8 +934,6 @@ struct cpu_features /* The full state size for XSAVE when XSAVEC is disabled by GLIBC_TUNABLES=glibc.cpu.hwcaps=-XSAVEC - - and the AMX state size when XSAVEC is available. */ unsigned int xsave_state_full_size; /* Data cache size for use in memory and string routines, typically @@ -989,6 +987,13 @@ extern const struct cpu_features *_dl_x86_get_cpu_features (void) #define __get_cpu_features() _dl_x86_get_cpu_features() +#if IS_IN (rtld) || IS_IN (libc) +/* XSAVE/XSAVEC state size used by TLS descriptors. Compared to + xsave_state_size from struct cpu_features, this includes additional + registers. */ +extern unsigned long int _dl_x86_features_tlsdesc_state_size attribute_hidden; +#endif + #if defined (_LIBC) && !IS_IN (nonlib) /* Unused for x86. */ # define INIT_ARCH() diff --git a/sysdeps/x86/tst-gnu2-tls2-x86-noxsave.c b/sysdeps/x86/tst-gnu2-tls2-x86-noxsave.c new file mode 100644 index 0000000..f0024c1 --- /dev/null +++ b/sysdeps/x86/tst-gnu2-tls2-x86-noxsave.c @@ -0,0 +1 @@ +#include <elf/tst-gnu2-tls2.c> diff --git a/sysdeps/x86/tst-gnu2-tls2-x86-noxsavec.c b/sysdeps/x86/tst-gnu2-tls2-x86-noxsavec.c new file mode 100644 index 0000000..f0024c1 --- /dev/null +++ b/sysdeps/x86/tst-gnu2-tls2-x86-noxsavec.c @@ -0,0 +1 @@ +#include <elf/tst-gnu2-tls2.c> diff --git a/sysdeps/x86/tst-gnu2-tls2-x86-noxsavexsavec.c b/sysdeps/x86/tst-gnu2-tls2-x86-noxsavexsavec.c new file mode 100644 index 0000000..f0024c1 --- /dev/null +++ b/sysdeps/x86/tst-gnu2-tls2-x86-noxsavexsavec.c @@ -0,0 +1 @@ +#include <elf/tst-gnu2-tls2.c> diff --git a/sysdeps/x86_64/dl-tlsdesc-dynamic.h b/sysdeps/x86_64/dl-tlsdesc-dynamic.h index 9f02cfc..44d9486 100644 --- a/sysdeps/x86_64/dl-tlsdesc-dynamic.h +++ b/sysdeps/x86_64/dl-tlsdesc-dynamic.h @@ -99,7 +99,7 @@ _dl_tlsdesc_dynamic: # endif #else /* Allocate stack space of the required size to save the state. */ - sub _rtld_local_ro+RTLD_GLOBAL_RO_DL_X86_CPU_FEATURES_OFFSET+XSAVE_STATE_FULL_SIZE_OFFSET(%rip), %RSP_LP + sub _dl_x86_features_tlsdesc_state_size(%rip), %RSP_LP #endif /* Besides rdi and rsi, saved above, save rcx, rdx, r8, r9, r10 and r11. */ |