Fix ssbd.c which depends implicitly on asm/ptrace.h including
linux/prctl.h (through for example linux/compat.h, then linux/time.h,
linux/seqlock.h, linux/spinlock.h and linux/irqflags.h), and uses
PR_SPEC* defines.
This is an issue since we'll remove the include in the next commit.
Fixes: 9cdc0108baa8 ("arm64: ssbd: Add prctl interface for per-thread mitigation")
Cc: [email protected]
Signed-off-by: Anisse Astier <[email protected]>
---
Contrary to what I said in the previous email, I can reproduce the build
error on Linus' master when ARM64_SSBD is enabled.
Changes since v2:
- fix build when ARM64_SSBD is enabled with additionnal patch
Changes since v1:
- made a bit more explicit that we copied defined symbols, in commit
and code.
- Use Fixes: tag in commit message
Thanks to Dave Martin and Will Deacon for the review, and Sasha Levin
for the auto-build bot.
---
arch/arm64/kernel/ssbd.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/kernel/ssbd.c b/arch/arm64/kernel/ssbd.c
index 885f13e58708..52cfc6148355 100644
--- a/arch/arm64/kernel/ssbd.c
+++ b/arch/arm64/kernel/ssbd.c
@@ -5,6 +5,7 @@
#include <linux/compat.h>
#include <linux/errno.h>
+#include <linux/prctl.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <linux/thread_info.h>
--
2.19.1
Otherwise this will create userspace build issues for any program
(strace, qemu) that includes both <sys/prctl.h> (with musl libc) and
<linux/ptrace.h> (which then includes <asm/ptrace.h>), like this:
error: redefinition of 'struct prctl_mm_map'
struct prctl_mm_map {
See https://github.com/foundriesio/meta-lmp/commit/6d4a106e191b5d79c41b9ac78fd321316d3013c0
for a public example of people working around this issue.
Copying the defines is a bit imperfect here, but better than creating a
whole other header for just two defines that would never change, as part
of the kernel ABI.
This patch depends on patch "arm64: ssbd: explicitly depend on
<linux/prctl.h>" for kernel >= 4.18
Fixes: 43d4da2c45b2 ("arm64/sve: ptrace and ELF coredump support")
Cc: [email protected]
Signed-off-by: Anisse Astier <[email protected]>
---
arch/arm64/include/uapi/asm/ptrace.h | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h
index 97c53203150b..e932284993d4 100644
--- a/arch/arm64/include/uapi/asm/ptrace.h
+++ b/arch/arm64/include/uapi/asm/ptrace.h
@@ -65,8 +65,6 @@
#ifndef __ASSEMBLY__
-#include <linux/prctl.h>
-
/*
* User structures for general purpose, floating point and debug registers.
*/
@@ -113,10 +111,10 @@ struct user_sve_header {
/*
* Common SVE_PT_* flags:
- * These must be kept in sync with prctl interface in <linux/ptrace.h>
+ * These must be kept in sync with prctl interface in <linux/prctl.h>
*/
-#define SVE_PT_VL_INHERIT (PR_SVE_VL_INHERIT >> 16)
-#define SVE_PT_VL_ONEXEC (PR_SVE_SET_VL_ONEXEC >> 16)
+#define SVE_PT_VL_INHERIT ((1 << 17) /* PR_SVE_VL_INHERIT */ >> 16)
+#define SVE_PT_VL_ONEXEC ((1 << 18) /* PR_SVE_SET_VL_ONEXEC */ >> 16)
/*
--
2.19.1
On Mon, Jun 17, 2019 at 03:22:22PM +0200, Anisse Astier wrote:
> Otherwise this will create userspace build issues for any program
> (strace, qemu) that includes both <sys/prctl.h> (with musl libc) and
> <linux/ptrace.h> (which then includes <asm/ptrace.h>), like this:
>
> error: redefinition of 'struct prctl_mm_map'
> struct prctl_mm_map {
>
> See https://github.com/foundriesio/meta-lmp/commit/6d4a106e191b5d79c41b9ac78fd321316d3013c0
> for a public example of people working around this issue.
>
> Copying the defines is a bit imperfect here, but better than creating a
> whole other header for just two defines that would never change, as part
> of the kernel ABI.
>
> This patch depends on patch "arm64: ssbd: explicitly depend on
> <linux/prctl.h>" for kernel >= 4.18
>
> Fixes: 43d4da2c45b2 ("arm64/sve: ptrace and ELF coredump support")
> Cc: [email protected]
> Signed-off-by: Anisse Astier <[email protected]>
> ---
> arch/arm64/include/uapi/asm/ptrace.h | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
I've pushed these two out to the arm64 fixes branch [1], with Dave's Ack
on this one. Note that I reworked the commit messages a bit to explain
better what's going on.
Cheers,
Will
[1] https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/log/?h=for-next/fixes