This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
[RFC PATCH v3 28/28] arm64/sve: signal: Include SVE when computing AT_MINSIGSTKSZ
- From: Dave Martin <Dave dot Martin at arm dot com>
- To: linux-arm-kernel at lists dot infradead dot org
- Cc: Catalin Marinas <catalin dot marinas at arm dot com>, Will Deacon <will dot deacon at arm dot com>, Ard Biesheuvel <ard dot biesheuvel at linaro dot org>, Alex Bennée <alex dot bennee at linaro dot org>, Szabolcs Nagy <szabolcs dot nagy at arm dot com>, Richard Sandiford <richard dot sandiford at arm dot com>, Okamoto Takayuki <tokamoto at jp dot fujitsu dot com>, kvmarm at lists dot cs dot columbia dot edu, libc-alpha at sourceware dot org, linux-arch at vger dot kernel dot org
- Date: Tue, 10 Oct 2017 19:38:45 +0100
- Subject: [RFC PATCH v3 28/28] arm64/sve: signal: Include SVE when computing AT_MINSIGSTKSZ
- Authentication-results: sourceware.org; auth=none
- References: <1507660725-7986-1-git-send-email-Dave.Martin@arm.com>
The SVE context block in the signal frame needs to be considered
too when computing the maximum possible signal frame size.
Because the size of this block depends on the vector length, this
patch computes the size based not on the thread's current vector
length but instead on the maximum possible vector length: this
determines the maximum size of SVE context block that can be
observed in any signal frame for the lifetime of the process.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Alex Bennée <alex.bennee@linaro.org>
---
arch/arm64/kernel/signal.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 3382e87..15bc2ad 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -595,8 +595,18 @@ static int setup_sigframe_layout(struct rt_sigframe_user_layout *user,
if (system_supports_sve()) {
unsigned int vq = 0;
- if (test_thread_flag(TIF_SVE))
- vq = sve_vq_from_vl(current->thread.sve_vl);
+ if (add_all || test_thread_flag(TIF_SVE)) {
+ int vl = sve_max_vl;
+
+ if (!add_all)
+ vl = current->thread.sve_vl;
+
+ /* Fail safe if something wasn't initialised */
+ if (WARN_ON(!sve_vl_valid(vl)))
+ vl = SVE_VL_MIN;
+
+ vq = sve_vq_from_vl(vl);
+ }
err = sigframe_alloc(user, &user->sve_offset,
SVE_SIG_CONTEXT_SIZE(vq));
--
2.1.4