* [PATCH v3] x86-64: Allocate state buffer space for RDI, RSI and RBX
@ 2024-03-17 11:37 H.J. Lu
0 siblings, 0 replies; only message in thread
From: H.J. Lu @ 2024-03-17 11:37 UTC (permalink / raw)
To: libc-alpha; +Cc: fweimer
_dl_tlsdesc_dynamic preserves RDI, RSI and RBX before realigning stack.
After realigning stack, it saves RCX, RDX, R8, R9, R10 and R11. Define
TLSDESC_CALL_REGISTER_SAVE_AREA to allocate space for RDI, RSI and RBX
to avoid clobbering saved RDI, RSI and RBX values on stack by xsave to
STATE_SAVE_OFFSET(%rsp).
+==================+<- stack frame start aligned at 8 or 16 bytes
| |<- RDI
| |<- RSI
| |<- RBX
| |<- paddings from stack realignment of 64 bytes
|------------------|<- xsave buffer end aligned at 64 bytes
| |<-
| |<-
| |<-
|------------------|<- xsave buffer start at STATE_SAVE_OFFSET(%rsp)
| |<- 8-byte padding
| |<- 8-byte padding
| |<- R11
| |<- R10
| |<- R9
| |<- R8
| |<- RDX
| |<- RCX
+==================+<- State buffer start aligned at 64 bytes
This fixes BZ #31501.
---
sysdeps/x86/cpu-features.c | 11 ++-
sysdeps/x86/sysdep.h | 29 ++++++++
sysdeps/x86_64/Makefile | 19 +++++
sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod0.c | 19 +++++
sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod1.S | 87 ++++++++++++++++++++++
sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod2.c | 19 +++++
sysdeps/x86_64/tst-gnu2-tls2-x86-64.c | 21 ++++++
7 files changed, 201 insertions(+), 4 deletions(-)
create mode 100644 sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod0.c
create mode 100644 sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod1.S
create mode 100644 sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod2.c
create mode 100644 sysdeps/x86_64/tst-gnu2-tls2-x86-64.c
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
index 4ea373dffa..3d7c2819d7 100644
--- a/sysdeps/x86/cpu-features.c
+++ b/sysdeps/x86/cpu-features.c
@@ -311,7 +311,7 @@ update_active (struct cpu_features *cpu_features)
/* NB: On AMX capable processors, ebx always includes AMX
states. */
unsigned int xsave_state_full_size
- = ALIGN_UP (ebx + STATE_SAVE_OFFSET, 64);
+ = ALIGN_UP (ebx + TLSDESC_CALL_REGISTER_SAVE_AREA, 64);
cpu_features->xsave_state_size
= xsave_state_full_size;
@@ -401,8 +401,10 @@ update_active (struct cpu_features *cpu_features)
unsigned int amx_size
= (xstate_amx_comp_offsets[31]
+ xstate_amx_comp_sizes[31]);
- amx_size = ALIGN_UP (amx_size + STATE_SAVE_OFFSET,
- 64);
+ amx_size
+ = 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
@@ -410,7 +412,8 @@ update_active (struct cpu_features *cpu_features)
cpu_features->xsave_state_full_size = amx_size;
#endif
cpu_features->xsave_state_size
- = ALIGN_UP (size + STATE_SAVE_OFFSET, 64);
+ = ALIGN_UP (size + TLSDESC_CALL_REGISTER_SAVE_AREA,
+ 64);
CPU_FEATURE_SET (cpu_features, XSAVEC);
}
}
diff --git a/sysdeps/x86/sysdep.h b/sysdeps/x86/sysdep.h
index db8e576e91..46fcd27345 100644
--- a/sysdeps/x86/sysdep.h
+++ b/sysdeps/x86/sysdep.h
@@ -46,6 +46,34 @@
red-zone into account. */
# define STATE_SAVE_OFFSET (8 * 7 + 8)
+/* _dl_tlsdesc_dynamic preserves RDI, RSI and RBX before realigning
+ stack. After realigning stack, it saves RCX, RDX, R8, R9, R10 and
+ R11. Allocate space for RDI, RSI and RBX to avoid clobbering saved
+ RDI, RSI and RBX values on stack by xsave.
+
+ +==================+<- stack frame start aligned at 8 or 16 bytes
+ | |<- RDI
+ | |<- RSI
+ | |<- RBX
+ | |<- paddings from stack realignment of 64 bytes
+ |------------------|<- xsave buffer end aligned at 64 bytes
+ | |<-
+ | |<-
+ | |<-
+ |------------------|<- xsave buffer start at STATE_SAVE_OFFSET(%rsp)
+ | |<- 8-byte padding
+ | |<- 8-byte padding
+ | |<- R11
+ | |<- R10
+ | |<- R9
+ | |<- R8
+ | |<- RDX
+ | |<- RCX
+ +==================+<- State buffer start aligned at 64 bytes
+
+*/
+# define TLSDESC_CALL_REGISTER_SAVE_AREA (STATE_SAVE_OFFSET + 24)
+
/* Save SSE, AVX, AVX512, mask, bound and APX registers. Bound and APX
registers are mutually exclusive. */
# define STATE_SAVE_MASK \
@@ -68,6 +96,7 @@
/* Offset for fxsave/xsave area used by _dl_tlsdesc_dynamic. Since i386
doesn't have red-zone, use 0 here. */
# define STATE_SAVE_OFFSET 0
+# define TLSDESC_CALL_REGISTER_SAVE_AREA 0
/* Save SSE, AVX, AXV512, mask and bound registers. */
# define STATE_SAVE_MASK \
diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
index 66b21954f3..e21e4b96ab 100644
--- a/sysdeps/x86_64/Makefile
+++ b/sysdeps/x86_64/Makefile
@@ -217,6 +217,25 @@ valgrind-suppressions-tst-valgrind-smoke = \
--suppressions=$(..)sysdeps/x86_64/tst-valgrind-smoke.supp
endif
+tests += \
+ tst-gnu2-tls2-x86-64 \
+# tests
+
+modules-names += \
+ tst-gnu2-tls2-x86-64-mod0 \
+ tst-gnu2-tls2-x86-64-mod1 \
+ tst-gnu2-tls2-x86-64-mod2 \
+# modules-names
+
+$(objpfx)tst-gnu2-tls2-x86-64: $(shared-thread-library)
+$(objpfx)tst-gnu2-tls2-x86-64.out: \
+ $(objpfx)tst-gnu2-tls2-x86-64-mod0.so \
+ $(objpfx)tst-gnu2-tls2-x86-64-mod1.so \
+ $(objpfx)tst-gnu2-tls2-x86-64-mod2.so
+
+CFLAGS-tst-gnu2-tls2-x86-64-mod0.c += -mtls-dialect=gnu2
+CFLAGS-tst-gnu2-tls2-x86-64-mod2.c += -mtls-dialect=gnu2
+
endif # $(subdir) == elf
ifeq ($(subdir),csu)
diff --git a/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod0.c b/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod0.c
new file mode 100644
index 0000000000..40b3ec5c82
--- /dev/null
+++ b/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod0.c
@@ -0,0 +1,19 @@
+/* DSO used by tst-gnu2-tls2-x86-64.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <tst-gnu2-tls2mod0.c>
diff --git a/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod1.S b/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod1.S
new file mode 100644
index 0000000000..449ddd5c9d
--- /dev/null
+++ b/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod1.S
@@ -0,0 +1,87 @@
+/* Check if TLSDESC relocation preserves %rdi, %rsi and %rbx.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* On AVX512 machines, OFFSET == 104 caused _dl_tlsdesc_dynamic_xsavec
+ to clobber %rdi, %rsi and %rbx. On Intel AVX CPUs, the state size
+ is 960 bytes and this test didn't fail. It may be due to the unused
+ last 128 bytes. On AMD AVX CPUs, the state size is 832 bytes and
+ this test might fail without the fix. */
+#ifndef OFFSET
+# define OFFSET 104
+#endif
+
+ .text
+ .p2align 4
+ .globl apply_tls
+ .type apply_tls, @function
+apply_tls:
+ cfi_startproc
+ _CET_ENDBR
+ pushq %rbp
+ cfi_def_cfa_offset (16)
+ cfi_offset (6, -16)
+ movdqu (%RDI_LP), %xmm0
+ lea tls_var1@TLSDESC(%rip), %RAX_LP
+ mov %RSP_LP, %RBP_LP
+ cfi_def_cfa_register (6)
+ /* Align stack to 64 bytes. */
+ and $-64, %RSP_LP
+ sub $OFFSET, %RSP_LP
+ pushq %rbx
+ /* Set %ebx to 0xbadbeef. */
+ movl $0xbadbeef, %ebx
+ movl $0xbadbeef, %esi
+ movq %rdi, saved_rdi(%rip)
+ movq %rsi, saved_rsi(%rip)
+ call *tls_var1@TLSCALL(%RAX_LP)
+ /* Check if _dl_tlsdesc_dynamic preserves %rdi, %rsi and %rbx. */
+ cmpq saved_rdi(%rip), %rdi
+ jne L(hlt)
+ cmpq saved_rsi(%rip), %rsi
+ jne L(hlt)
+ cmpl $0xbadbeef, %ebx
+ jne L(hlt)
+ add %fs:0, %RAX_LP
+ movups %xmm0, 32(%RAX_LP)
+ movdqu 16(%RDI_LP), %xmm1
+ mov %RAX_LP, %RBX_LP
+ movups %xmm1, 48(%RAX_LP)
+ lea 32(%RBX_LP), %RAX_LP
+ pop %rbx
+ leave
+ cfi_def_cfa (7, 8)
+ ret
+L(hlt):
+ hlt
+ cfi_endproc
+ .size apply_tls, .-apply_tls
+ .hidden tls_var1
+ .globl tls_var1
+ .section .tbss,"awT",@nobits
+ .align 16
+ .type tls_var1, @object
+ .size tls_var1, 3200
+tls_var1:
+ .zero 3200
+ .local saved_rdi
+ .comm saved_rdi,8,8
+ .local saved_rsi
+ .comm saved_rsi,8,8
+ .section .note.GNU-stack,"",@progbits
diff --git a/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod2.c b/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod2.c
new file mode 100644
index 0000000000..c12b81a49b
--- /dev/null
+++ b/sysdeps/x86_64/tst-gnu2-tls2-x86-64-mod2.c
@@ -0,0 +1,19 @@
+/* DSO used by tst-gnu2-tls2-x86-64.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <tst-gnu2-tls2mod2.c>
diff --git a/sysdeps/x86_64/tst-gnu2-tls2-x86-64.c b/sysdeps/x86_64/tst-gnu2-tls2-x86-64.c
new file mode 100644
index 0000000000..7d51f488bd
--- /dev/null
+++ b/sysdeps/x86_64/tst-gnu2-tls2-x86-64.c
@@ -0,0 +1,21 @@
+/* Check if TLSDESC relocation preserves %rdi, %rsi and %rbx.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#define MOD(i) "tst-gnu2-tls2-x86-64-mod" #i ".so"
+
+#include <elf/tst-gnu2-tls2.c>
--
2.44.0
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