Linux build: silence objtool warnings

After #17401 the Linux build produces some stack related warnings.

Silence them with the `STACK_FRAME_NON_STANDARD` macro.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #17410

config/kernel-objtool.m4

@@ -11,10 +11,12 @@ AC_DEFUN([ZFS_AC_KERNEL_OBJTOOL_HEADER], [
 		#include <linux/objtool.h>
 	],[
 	],[
+		objtool_header=$LINUX/include/linux/objtool.h
 		AC_DEFINE(HAVE_KERNEL_OBJTOOL_HEADER, 1,
 		    [kernel has linux/objtool.h])
 		AC_MSG_RESULT(linux/objtool.h)
 	],[
+		objtool_header=$LINUX/include/linux/frame.h
 		AC_MSG_RESULT(linux/frame.h)
 	])
 ])
@@ -62,6 +64,23 @@ AC_DEFUN([ZFS_AC_KERNEL_OBJTOOL], [
 			AC_MSG_RESULT(yes)
 			AC_DEFINE(HAVE_STACK_FRAME_NON_STANDARD, 1,
 			   [STACK_FRAME_NON_STANDARD is defined])
+
+			dnl # Needed for kernels missing the asm macro. We grep
+			dnl # for it in the header file since there is currently
+			dnl # no test to check the result of assembling a file.
+			AC_MSG_CHECKING(
+			    [whether STACK_FRAME_NON_STANDARD asm macro is defined])
+			dnl # Escape square brackets.
+			sp='@<:@@<:@:space:@:>@@:>@'
+			dotmacro='@<:@.@:>@macro'
+			regexp="^$sp*$dotmacro$sp+STACK_FRAME_NON_STANDARD$sp"
+			AS_IF([$EGREP -s -q "$regexp" $objtool_header],[
+				AC_MSG_RESULT(yes)
+				AC_DEFINE(HAVE_STACK_FRAME_NON_STANDARD_ASM, 1,
+				   [STACK_FRAME_NON_STANDARD asm macro is defined])
+			],[
+				AC_MSG_RESULT(no)
+			])
 		],[
 			AC_MSG_RESULT(no)
 		])

include/sys/frame.h

@@ -31,8 +31,16 @@ extern "C" {
 #else
 #include <linux/frame.h>
 #endif
+#if defined(_ASM) && ! defined(HAVE_STACK_FRAME_NON_STANDARD_ASM)
+.macro STACK_FRAME_NON_STANDARD func:req
+.endm
+#endif
 #else
 #define	STACK_FRAME_NON_STANDARD(func)
+#if defined(_ASM)
+.macro STACK_FRAME_NON_STANDARD func:req
+.endm
+#endif
 #endif
 
 #ifdef	__cplusplus

module/icp/asm-x86_64/modes/aesni-gcm-x86_64.S

@@ -50,6 +50,7 @@
 
 #define _ASM
 #include <sys/asm_linkage.h>
+#include <sys/frame.h>
 
 /* Windows userland links with OpenSSL */
 #if !defined (_WIN32) || defined (_KERNEL)
@@ -378,6 +379,7 @@ FUNCTION(_aesni_ctr32_ghash_6x)
 	RET
 .cfi_endproc
 SET_SIZE(_aesni_ctr32_ghash_6x)
+STACK_FRAME_NON_STANDARD _aesni_ctr32_ghash_6x
 #endif /* ifdef HAVE_MOVBE */
 
 .balign 32
@@ -706,6 +708,7 @@ FUNCTION(_aesni_ctr32_ghash_no_movbe_6x)
 	RET
 .cfi_endproc
 SET_SIZE(_aesni_ctr32_ghash_no_movbe_6x)
+STACK_FRAME_NON_STANDARD _aesni_ctr32_ghash_no_movbe_6x
 
 ENTRY_ALIGN(aesni_gcm_decrypt, 32)
 .cfi_startproc
@@ -823,6 +826,7 @@ ENTRY_ALIGN(aesni_gcm_decrypt, 32)
 	RET
 .cfi_endproc
 SET_SIZE(aesni_gcm_decrypt)
+STACK_FRAME_NON_STANDARD aesni_gcm_decrypt
 
 .balign 32
 FUNCTION(_aesni_ctr32_6x)
@@ -1198,6 +1202,7 @@ ENTRY_ALIGN(aesni_gcm_encrypt, 32)
 	RET
 .cfi_endproc
 SET_SIZE(aesni_gcm_encrypt)
+STACK_FRAME_NON_STANDARD aesni_gcm_encrypt
 
 #endif /* !_WIN32 || _KERNEL */
 
@@ -1257,6 +1262,18 @@ SECTION_STATIC
 .byte	65,69,83,45,78,73,32,71,67,77,32,109,111,100,117,108,101,32,102,111,114,32,120,56,54,95,54,52,44,32,67,82,89,80,84,79,71,65,77,83,32,98,121,32,60,97,112,112,114,111,64,111,112,101,110,115,115,108,46,111,114,103,62,0
 .balign	64
 
+/* Workaround for missing asm macro in RHEL 8. */
+#if defined(__linux__) && defined(HAVE_STACK_FRAME_NON_STANDARD) && \
+    ! defined(HAVE_STACK_FRAME_NON_STANDARD_ASM)
+.section .discard.func_stack_frame_non_standard, "aw"
+#ifdef HAVE_MOVBE
+	.long _aesni_ctr32_ghash_6x  - .
+#endif
+	.long _aesni_ctr32_ghash_no_movbe_6x - .
+	.long aesni_gcm_decrypt - .
+	.long aesni_gcm_encrypt - .
+#endif
+
 /* Mark the stack non-executable. */
 #if defined(__linux__) && defined(__ELF__)
 .section .note.GNU-stack,"",%progbits

module/icp/asm-x86_64/sha2/sha256-x86_64.S

@@ -24,6 +24,7 @@
 
 #define _ASM
 #include <sys/asm_linkage.h>
+#include <sys/frame.h>
 
 SECTION_STATIC
 
@@ -1420,6 +1421,7 @@ ENTRY_ALIGN(zfs_sha256_transform_x64, 16)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha256_transform_x64)
+STACK_FRAME_NON_STANDARD zfs_sha256_transform_x64
 
 ENTRY_ALIGN(zfs_sha256_transform_shani, 64)
 .cfi_startproc
@@ -1628,6 +1630,7 @@ ENTRY_ALIGN(zfs_sha256_transform_shani, 64)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha256_transform_shani)
+STACK_FRAME_NON_STANDARD zfs_sha256_transform_shani
 
 ENTRY_ALIGN(zfs_sha256_transform_ssse3, 64)
 .cfi_startproc
@@ -2739,6 +2742,7 @@ ENTRY_ALIGN(zfs_sha256_transform_ssse3, 64)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha256_transform_ssse3)
+STACK_FRAME_NON_STANDARD zfs_sha256_transform_ssse3
 
 ENTRY_ALIGN(zfs_sha256_transform_avx, 64)
 .cfi_startproc
@@ -3813,6 +3817,7 @@ ENTRY_ALIGN(zfs_sha256_transform_avx, 64)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha256_transform_avx)
+STACK_FRAME_NON_STANDARD zfs_sha256_transform_avx
 
 ENTRY_ALIGN(zfs_sha256_transform_avx2, 64)
 .cfi_startproc
@@ -5098,6 +5103,18 @@ ENTRY_ALIGN(zfs_sha256_transform_avx2, 64)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha256_transform_avx2)
+STACK_FRAME_NON_STANDARD zfs_sha256_transform_avx2
+
+/* Workaround for missing asm macro in RHEL 8. */
+#if defined(__linux__) && defined(HAVE_STACK_FRAME_NON_STANDARD) && \
+    ! defined(HAVE_STACK_FRAME_NON_STANDARD_ASM)
+.section .discard.func_stack_frame_non_standard, "aw"
+	.long zfs_sha256_transform_x64 - .
+	.long zfs_sha256_transform_shani - .
+	.long zfs_sha256_transform_ssse3 - .
+	.long zfs_sha256_transform_avx - .
+	.long zfs_sha256_transform_avx2 - .
+#endif
 
 #if defined(__ELF__)
 	.section .note.GNU-stack,"",%progbits

module/icp/asm-x86_64/sha2/sha512-x86_64.S

@@ -24,6 +24,7 @@
 
 #define _ASM
 #include <sys/asm_linkage.h>
+#include <sys/frame.h>
 
 SECTION_STATIC
 
@@ -1463,6 +1464,7 @@ ENTRY_ALIGN(zfs_sha512_transform_x64, 16)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha512_transform_x64)
+STACK_FRAME_NON_STANDARD zfs_sha512_transform_x64
 
 ENTRY_ALIGN(zfs_sha512_transform_avx, 64)
 .cfi_startproc
@@ -2627,6 +2629,7 @@ ENTRY_ALIGN(zfs_sha512_transform_avx, 64)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha512_transform_avx)
+STACK_FRAME_NON_STANDARD zfs_sha512_transform_avx
 
 ENTRY_ALIGN(zfs_sha512_transform_avx2, 64)
 .cfi_startproc
@@ -4005,6 +4008,16 @@ ENTRY_ALIGN(zfs_sha512_transform_avx2, 64)
 	RET
 .cfi_endproc
 SET_SIZE(zfs_sha512_transform_avx2)
+STACK_FRAME_NON_STANDARD zfs_sha512_transform_avx2
+
+/* Workaround for missing asm macro in RHEL 8. */
+#if defined(__linux__) && defined(HAVE_STACK_FRAME_NON_STANDARD) && \
+    ! defined(HAVE_STACK_FRAME_NON_STANDARD_ASM)
+.section .discard.func_stack_frame_non_standard, "aw"
+	.long zfs_sha512_transform_x64 - .
+	.long zfs_sha512_transform_avx - .
+	.long zfs_sha512_transform_avx2 - .
+#endif
 
 #if defined(__ELF__)
 	.section .note.GNU-stack,"",%progbits