From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Nathan Chancellor <nathan@kernel.org>,
Fangrui Song <maskray@google.com>,
Palmer Dabbelt <palmerdabbelt@google.com>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.10 23/47] riscv: Use $(LD) instead of $(CC) to link vDSO
Date: Thu, 20 May 2021 11:22:21 +0200 [thread overview]
Message-ID: <20210520092054.292173621@linuxfoundation.org> (raw)
In-Reply-To: <20210520092053.559923764@linuxfoundation.org>
From: Nathan Chancellor <nathan@kernel.org>
[ Upstream commit 7f3d349065d0c643f7f7013fbf9bc9f2c90b675f ]
Currently, the VDSO is being linked through $(CC). This does not match
how the rest of the kernel links objects, which is through the $(LD)
variable.
When linking with clang, there are a couple of warnings about flags that
will not be used during the link:
clang-12: warning: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument]
clang-12: warning: argument unused during compilation: '-pg' [-Wunused-command-line-argument]
'-no-pie' was added in commit 85602bea297f ("RISC-V: build vdso-dummy.o
with -no-pie") to override '-pie' getting added to the ld command from
distribution versions of GCC that enable PIE by default. It is
technically no longer needed after commit c2c81bb2f691 ("RISC-V: Fix the
VDSO symbol generaton for binutils-2.35+"), which removed vdso-dummy.o
in favor of generating vdso-syms.S from vdso.so with $(NM) but this also
resolves the issue in case it ever comes back due to having full control
over the $(LD) command. '-pg' is for function tracing, it is not used
during linking as clang states.
These flags could be removed/filtered to fix the warnings but it is
easier to just match the rest of the kernel and use $(LD) directly for
linking. See commits
fe00e50b2db8 ("ARM: 8858/1: vdso: use $(LD) instead of $(CC) to link VDSO")
691efbedc60d ("arm64: vdso: use $(LD) instead of $(CC) to link VDSO")
2ff906994b6c ("MIPS: VDSO: Use $(LD) instead of $(CC) to link VDSO")
2b2a25845d53 ("s390/vdso: Use $(LD) instead of $(CC) to link vDSO")
for more information.
The flags are converted to linker flags and '--eh-frame-hdr' is added to
match what is added by GCC implicitly, which can be seen by adding '-v'
to GCC's invocation.
Additionally, since this area is being modified, use the $(OBJCOPY)
variable instead of an open coded $(CROSS_COMPILE)objcopy so that the
user's choice of objcopy binary is respected.
Link: https://github.com/ClangBuiltLinux/linux/issues/803
Link: https://github.com/ClangBuiltLinux/linux/issues/970
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/riscv/kernel/vdso/Makefile | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index 71a315e73cbe..ca2b40dfd24b 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -41,11 +41,10 @@ KASAN_SANITIZE := n
$(obj)/vdso.o: $(obj)/vdso.so
# link rule for the .so file, .lds has to be first
-SYSCFLAGS_vdso.so.dbg = $(c_flags)
$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE
$(call if_changed,vdsold)
-SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
- -Wl,--build-id=sha1 -Wl,--hash-style=both
+LDFLAGS_vdso.so.dbg = -shared -s -soname=linux-vdso.so.1 \
+ --build-id=sha1 --hash-style=both --eh-frame-hdr
# We also create a special relocatable object that should mirror the symbol
# table and layout of the linked DSO. With ld --just-symbols we can then
@@ -60,13 +59,10 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
# actual build commands
# The DSO images are built using a special linker script
-# Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions.
# Make sure only to export the intended __vdso_xxx symbol offsets.
quiet_cmd_vdsold = VDSOLD $@
- cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \
- -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \
- $(CROSS_COMPILE)objcopy \
- $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \
+ cmd_vdsold = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \
+ $(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \
rm $@.tmp
# Extracts symbol offsets from the VDSO, converting them into an assembly file
--
2.30.2
next prev parent reply other threads:[~2021-05-20 9:29 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-20 9:21 [PATCH 5.10 00/47] 5.10.39-rc1 review Greg Kroah-Hartman
2021-05-20 9:21 ` [PATCH 5.10 01/47] x86/msr: Fix wr/rdmsr_safe_regs_on_cpu() prototypes Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 02/47] drm/i915/display: fix compiler warning about array overrun Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 03/47] airo: work around stack usage warning Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 04/47] kgdb: fix gcc-11 warning on indentation Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 05/47] usb: sl811-hcd: improve misleading indentation Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 06/47] cxgb4: Fix the -Wmisleading-indentation warning Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 07/47] isdn: capi: fix mismatched prototypes Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 08/47] virtio_net: Do not pull payload in skb->head Greg Kroah-Hartman
2021-05-20 9:22 ` Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 09/47] ARM: 9058/1: cache-v7: refactor v7_invalidate_l1 to avoid clobbering r5/r6 Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 10/47] PCI: thunder: Fix compile testing Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 11/47] dmaengine: dw-edma: Fix crash on loading/unloading driver Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 12/47] ARM: 9066/1: ftrace: pause/unpause function graph tracer in cpu_suspend() Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 13/47] ACPI / hotplug / PCI: Fix reference count leak in enable_slot() Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 14/47] PCI: tegra: Fix runtime PM imbalance in pex_ep_event_pex_rst_deassert() Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 15/47] Input: elants_i2c - do not bind to i2c-hid compatible ACPI instantiated devices Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 16/47] Input: silead - add workaround for x86 BIOS-es which bring the chip up in a stuck state Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 17/47] NFS: NFS_INO_REVAL_PAGECACHE should mark the change attribute invalid Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 18/47] um: Mark all kernel symbols as local Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 19/47] um: Disable CONFIG_GCOV with MODULES Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 20/47] PCI: tegra: Add Tegra194 MCFG quirks for ECAM errata Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 21/47] ARM: 9075/1: kernel: Fix interrupted SMC calls Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 22/47] platform/chrome: cros_ec_typec: Add DP mode check Greg Kroah-Hartman
2021-05-20 9:22 ` Greg Kroah-Hartman [this message]
2021-05-20 9:22 ` [PATCH 5.10 24/47] scripts/recordmcount.pl: Fix RISC-V regex for clang Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 25/47] riscv: Workaround mcount name prior to clang-13 Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 26/47] scsi: lpfc: Fix illegal memory access on Abort IOCBs Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 27/47] ceph: fix fscache invalidation Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 28/47] ceph: dont clobber i_snap_caps on non-I_NEW inode Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 29/47] ceph: dont allow access to MDS-private inodes Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 30/47] scsi: target: tcmu: Return from tcmu_handle_completions() if cmd_id not found Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 31/47] amdgpu/pm: Prevent force of DCEFCLK on NAVI10 and SIENNA_CICHLID Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 32/47] bridge: Fix possible races between assigning rx_handler_data and setting IFF_BRIDGE_PORT bit Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 33/47] net: hsr: check skb can contain struct hsr_ethhdr in fill_frame_info Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 34/47] nvmet: remove unsupported command noise Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 35/47] drm/amd/display: Fix two cursor duplication when using overlay Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 36/47] gpiolib: acpi: Add quirk to ignore EC wakeups on Dell Venue 10 Pro 5055 Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 37/47] net:CXGB4: fix leak if sk_buff is not used Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 38/47] ALSA: hda: generic: change the DAC ctl name for LO+SPK or LO+HP Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 39/47] block: reexpand iov_iter after read/write Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 40/47] lib: stackdepot: turn depot_lock spinlock to raw_spinlock Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 41/47] net: stmmac: Do not enable RX FIFO overflow interrupts Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 42/47] ip6_gre: proper dev_{hold|put} in ndo_[un]init methods Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 43/47] sit: " Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 44/47] ip6_tunnel: " Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 45/47] ipv6: remove extra dev_hold() for fallback tunnels Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 46/47] tweewide: Fix most Shebang lines Greg Kroah-Hartman
2021-05-20 9:22 ` [PATCH 5.10 47/47] scripts: switch explicitly to Python 3 Greg Kroah-Hartman
2021-05-20 11:24 ` [PATCH 5.10 00/47] 5.10.39-rc1 review Pavel Machek
2021-05-20 12:32 ` Jon Hunter
2021-05-20 12:59 ` Greg Kroah-Hartman
2021-05-20 14:07 ` Fox Chen
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