Greg Kroah-Hartman
598cf27219
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Luna Jernberg <droidbittin@gmail.com> Tested-by: Ronald Warsow <rwarsow@gmx.de> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Tested-by: Ron Economos <re@w6rz.net> Tested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
50 lines
882 B
ArmAsm
50 lines
882 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* thunks_32.S - assembly helpers for mixed-bitness code
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* Copyright (c) 2015 Denys Vlasenko
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*
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* These are little helpers that make it easier to switch bitness on
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* the fly.
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*/
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.text
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.code32
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.global call64_from_32
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.type call32_from_64, @function
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// 4(%esp): function to call
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call64_from_32:
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// Fetch function address
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mov 4(%esp), %eax
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// Save registers which are callee-clobbered by 64-bit ABI
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push %ecx
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push %edx
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push %esi
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push %edi
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// Switch to long mode
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jmp $0x33,$1f
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1: .code64
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// Call the function
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call *%rax
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// Switch to compatibility mode
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push $0x23 /* USER32_CS */
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.code32; push $1f; .code64 /* hack: can't have X86_64_32S relocation in 32-bit ELF */
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lretq
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1: .code32
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pop %edi
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pop %esi
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pop %edx
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pop %ecx
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ret
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.size call64_from_32, .-call64_from_32
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.section .note.GNU-stack,"",%progbits
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