From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>,
Sasha Levin <sashal@kernel.org>,
Fangrui Song <maskray@google.com>,
Ilie Halip <ilie.halip@gmail.com>,
Catalin Marinas <catalin.marinas@arm.com>,
clang-built-linux@googlegroups.com,
linux-arm-kernel@lists.infradead.org
Subject: [PATCH AUTOSEL 5.6 29/38] arm64: Delete the space separator in __emit_inst
Date: Fri, 24 Apr 2020 08:22:27 -0400 [thread overview]
Message-ID: <20200424122237.9831-29-sashal@kernel.org> (raw)
In-Reply-To: <20200424122237.9831-1-sashal@kernel.org>
From: Fangrui Song <maskray@google.com>
[ Upstream commit c9a4ef66450145a356a626c833d3d7b1668b3ded ]
In assembly, many instances of __emit_inst(x) expand to a directive. In
a few places __emit_inst(x) is used as an assembler macro argument. For
example, in arch/arm64/kvm/hyp/entry.S
ALTERNATIVE(nop, SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN)
expands to the following by the C preprocessor:
alternative_insn nop, .inst (0xd500401f | ((0) << 16 | (4) << 5) | ((!!1) << 8)), 4, 1
Both comma and space are separators, with an exception that content
inside a pair of parentheses/quotes is not split, so the clang
integrated assembler splits the arguments to:
nop, .inst, (0xd500401f | ((0) << 16 | (4) << 5) | ((!!1) << 8)), 4, 1
GNU as preprocesses the input with do_scrub_chars(). Its arm64 backend
(along with many other non-x86 backends) sees:
alternative_insn nop,.inst(0xd500401f|((0)<<16|(4)<<5)|((!!1)<<8)),4,1
# .inst(...) is parsed as one argument
while its x86 backend sees:
alternative_insn nop,.inst (0xd500401f|((0)<<16|(4)<<5)|((!!1)<<8)),4,1
# The extra space before '(' makes the whole .inst (...) parsed as two arguments
The non-x86 backend's behavior is considered unintentional
(https://sourceware.org/bugzilla/show_bug.cgi?id=25750).
So drop the space separator inside `.inst (...)` to make the clang
integrated assembler work.
Suggested-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/939
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arm64/include/asm/sysreg.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index b91570ff9db14..931037500e83c 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -49,7 +49,9 @@
#ifndef CONFIG_BROKEN_GAS_INST
#ifdef __ASSEMBLY__
-#define __emit_inst(x) .inst (x)
+// The space separator is omitted so that __emit_inst(x) can be parsed as
+// either an assembler directive or an assembler macro argument.
+#define __emit_inst(x) .inst(x)
#else
#define __emit_inst(x) ".inst " __stringify((x)) "\n\t"
#endif
--
2.20.1
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WARNING: multiple messages have this Message-ID (diff)
From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Fangrui Song <maskray@google.com>,
Ilie Halip <ilie.halip@gmail.com>,
Mark Rutland <mark.rutland@arm.com>,
Catalin Marinas <catalin.marinas@arm.com>,
Sasha Levin <sashal@kernel.org>,
linux-arm-kernel@lists.infradead.org,
clang-built-linux@googlegroups.com
Subject: [PATCH AUTOSEL 5.6 29/38] arm64: Delete the space separator in __emit_inst
Date: Fri, 24 Apr 2020 08:22:27 -0400 [thread overview]
Message-ID: <20200424122237.9831-29-sashal@kernel.org> (raw)
In-Reply-To: <20200424122237.9831-1-sashal@kernel.org>
From: Fangrui Song <maskray@google.com>
[ Upstream commit c9a4ef66450145a356a626c833d3d7b1668b3ded ]
In assembly, many instances of __emit_inst(x) expand to a directive. In
a few places __emit_inst(x) is used as an assembler macro argument. For
example, in arch/arm64/kvm/hyp/entry.S
ALTERNATIVE(nop, SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN)
expands to the following by the C preprocessor:
alternative_insn nop, .inst (0xd500401f | ((0) << 16 | (4) << 5) | ((!!1) << 8)), 4, 1
Both comma and space are separators, with an exception that content
inside a pair of parentheses/quotes is not split, so the clang
integrated assembler splits the arguments to:
nop, .inst, (0xd500401f | ((0) << 16 | (4) << 5) | ((!!1) << 8)), 4, 1
GNU as preprocesses the input with do_scrub_chars(). Its arm64 backend
(along with many other non-x86 backends) sees:
alternative_insn nop,.inst(0xd500401f|((0)<<16|(4)<<5)|((!!1)<<8)),4,1
# .inst(...) is parsed as one argument
while its x86 backend sees:
alternative_insn nop,.inst (0xd500401f|((0)<<16|(4)<<5)|((!!1)<<8)),4,1
# The extra space before '(' makes the whole .inst (...) parsed as two arguments
The non-x86 backend's behavior is considered unintentional
(https://sourceware.org/bugzilla/show_bug.cgi?id=25750).
So drop the space separator inside `.inst (...)` to make the clang
integrated assembler work.
Suggested-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/939
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arm64/include/asm/sysreg.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index b91570ff9db14..931037500e83c 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -49,7 +49,9 @@
#ifndef CONFIG_BROKEN_GAS_INST
#ifdef __ASSEMBLY__
-#define __emit_inst(x) .inst (x)
+// The space separator is omitted so that __emit_inst(x) can be parsed as
+// either an assembler directive or an assembler macro argument.
+#define __emit_inst(x) .inst(x)
#else
#define __emit_inst(x) ".inst " __stringify((x)) "\n\t"
#endif
--
2.20.1
next prev parent reply other threads:[~2020-04-24 12:23 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-24 12:21 [PATCH AUTOSEL 5.6 01/38] libbpf: Initialize *nl_pid so gcc 10 is happy Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 02/38] net: fec: set GPR bit on suspend by DT configuration Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 03/38] x86: hyperv: report value of misc_features Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 04/38] signal: check sig before setting info in kill_pid_usb_asyncio Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 05/38] hwmon: (drivetemp) Use drivetemp's true module name in Kconfig section Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 06/38] hwmon: (drivetemp) Return -ENODATA for invalid temperatures Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 07/38] afs: Fix length of dump of bad YFSFetchStatus record Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 08/38] xfs: acquire superblock freeze protection on eofblocks scans Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 09/38] xfs: fix partially uninitialized structure in xfs_reflink_remap_extent Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 10/38] ALSA: hda: Release resources at error in delayed probe Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 11/38] ALSA: hda: Keep the controller initialization even if no codecs found Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 12/38] ALSA: hda: Skip controller resume if not needed Sasha Levin
2020-04-24 12:44 ` Takashi Iwai
2020-04-24 12:44 ` Takashi Iwai
2020-04-30 22:36 ` Roy Spliet
2020-05-01 1:17 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 13/38] ALSA: hda: Explicitly permit using autosuspend if runtime PM is supported Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 14/38] drm/amdgpu: fix wrong vram lost counter increment V2 Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 15/38] scsi: target: fix PR IN / READ FULL STATUS for FC Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 16/38] scsi: target: tcmu: reset_ring should reset TCMU_DEV_BIT_BROKEN Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 17/38] clk: asm9260: fix __clk_hw_register_fixed_rate_with_accuracy typo Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 18/38] efi/x86: Don't remap text<->rodata gap read-only for mixed mode Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 19/38] objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 20/38] objtool: Support Clang non-section symbols in ORC dump Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 21/38] xen/xenbus: ensure xenbus_map_ring_valloc() returns proper grant status Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 22/38] ALSA: hda: call runtime_allow() for all hda controllers Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 23/38] net: stmmac: socfpga: Allow all RGMII modes Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 24/38] net/cxgb4: Check the return from t4_query_params properly Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 25/38] mac80211: fix channel switch trigger from unknown mesh peer Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 26/38] sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 27/38] sched/vtime: Work around an unitialized variable warning Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 28/38] i2c: remove i2c_new_probed_device API Sasha Levin
2020-04-24 13:36 ` Wolfram Sang
2020-04-25 1:51 ` Sasha Levin
2020-04-24 12:22 ` Sasha Levin [this message]
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 29/38] arm64: Delete the space separator in __emit_inst Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 30/38] i2c: tegra: Better handle case where CPU0 is busy for a long time Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-27 7:22 ` Thierry Reding
2020-04-27 7:22 ` Thierry Reding
2020-05-01 0:59 ` Sasha Levin
2020-05-01 0:59 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 31/38] i2c: tegra: Synchronize DMA before termination Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 32/38] ext4: use matching invalidatepage in ext4_writepage Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 33/38] ext4: increase wait time needed before reuse of deleted inode numbers Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 34/38] ext4: convert BUG_ON's to WARN_ON's in mballoc.c Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 35/38] irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 36/38] blk-mq: Put driver tag in blk_mq_dispatch_rq_list() when no budget Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 37/38] irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` Sasha Levin
2020-04-24 12:22 ` [PATCH AUTOSEL 5.6 38/38] hwmon: (jc42) Fix name to have no illegal characters Sasha Levin
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