From: "Christopher M. Riedl" <cmr@codefail.de>
To: linuxppc-dev@lists.ozlabs.org
Cc: Daniel Axtens <dja@axtens.net>
Subject: [PATCH v7 09/10] powerpc/signal64: Rewrite rt_sigreturn() to minimise uaccess switches
Date: Fri, 26 Feb 2021 19:12:58 -0600 [thread overview]
Message-ID: <20210227011259.11992-10-cmr@codefail.de> (raw)
In-Reply-To: <20210227011259.11992-1-cmr@codefail.de>
From: Daniel Axtens <dja@axtens.net>
Add uaccess blocks and use the 'unsafe' versions of functions doing user
access where possible to reduce the number of times uaccess has to be
opened/closed.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Co-developed-by: Christopher M. Riedl <cmr@codefail.de>
Signed-off-by: Christopher M. Riedl <cmr@codefail.de>
---
arch/powerpc/kernel/signal_64.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 788854734b9a..00c907022707 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -822,11 +822,11 @@ SYSCALL_DEFINE0(rt_sigreturn)
*/
current->thread.regs->msr &= ~MSR_TS_MASK;
if (!user_read_access_begin(&uc->uc_mcontext, sizeof(uc->uc_mcontext)))
- return -EFAULT;
- if (__unsafe_restore_sigcontext(current, NULL, 1, &uc->uc_mcontext)) {
- user_read_access_end();
goto badframe;
- }
+
+ unsafe_restore_sigcontext(current, NULL, 1, &uc->uc_mcontext,
+ badframe_block);
+
user_read_access_end();
}
@@ -836,6 +836,8 @@ SYSCALL_DEFINE0(rt_sigreturn)
set_thread_flag(TIF_RESTOREALL);
return 0;
+badframe_block:
+ user_read_access_end();
badframe:
signal_fault(current, regs, "rt_sigreturn", uc);
--
2.26.1
next prev parent reply other threads:[~2021-02-27 1:13 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-27 1:12 [PATCH v7 00/10] Improve signal performance on PPC64 with KUAP Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 01/10] powerpc/uaccess: Add unsafe_copy_from_user() Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 02/10] powerpc/signal: Add unsafe_copy_{vsx, fpr}_from_user() Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 03/10] powerpc/signal64: Remove non-inline calls from setup_sigcontext() Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 04/10] powerpc: Reference parameter in MSR_TM_ACTIVE() macro Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 05/10] powerpc/signal64: Remove TM ifdefery in middle of if/else block Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 06/10] powerpc/signal64: Replace setup_sigcontext() w/ unsafe_setup_sigcontext() Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 07/10] powerpc/signal64: Replace restore_sigcontext() w/ unsafe_restore_sigcontext() Christopher M. Riedl
2021-02-27 1:12 ` [PATCH v7 08/10] powerpc/signal64: Rewrite handle_rt_signal64() to minimise uaccess switches Christopher M. Riedl
2021-02-27 1:12 ` Christopher M. Riedl [this message]
2021-02-27 1:12 ` [PATCH v7 10/10] powerpc/signal: Use __get_user() to copy sigset_t Christopher M. Riedl
2021-03-31 1:09 ` [PATCH v7 00/10] Improve signal performance on PPC64 with KUAP Michael Ellerman
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