From: Benjamin Berg <benjamin@sipsolutions.net>
To: linux-um@lists.infradead.org
Cc: Benjamin Berg <benjamin.berg@intel.com>
Subject: [PATCH v9 05/10] um: Add compile time assert that stub fits on a page
Date: Thu, 19 Sep 2024 14:45:06 +0200 [thread overview]
Message-ID: <20240919124511.282088-6-benjamin@sipsolutions.net> (raw)
In-Reply-To: <20240919124511.282088-1-benjamin@sipsolutions.net>
From: Benjamin Berg <benjamin.berg@intel.com>
The code assumes that the stub code can fit into a single page. This is
unlikely to ever change, but add a link time assert instead so that
there will be no hard to debug error.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
---
arch/um/kernel/dyn.lds.S | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/um/kernel/dyn.lds.S b/arch/um/kernel/dyn.lds.S
index 3385d653ebd0..dc9d9a68af55 100644
--- a/arch/um/kernel/dyn.lds.S
+++ b/arch/um/kernel/dyn.lds.S
@@ -178,3 +178,6 @@ SECTIONS
DISCARDS
}
+
+ASSERT(__syscall_stub_end - __syscall_stub_start <= PAGE_SIZE,
+ "STUB code must not be larger than one page");
--
2.46.0
next prev parent reply other threads:[~2024-09-19 12:45 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-09-19 12:45 [PATCH v9 00/10] Increased address space for 64 bit Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 01/10] um: Add generic stub_syscall1 function Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 02/10] um: use execveat to create userspace MMs Benjamin Berg
2024-10-16 2:34 ` Nathan Chancellor
2024-10-16 8:19 ` Berg, Benjamin
2024-10-17 7:17 ` David Gow
2024-10-17 8:18 ` Johannes Berg
2024-10-17 12:05 ` Benjamin Berg
2024-10-17 23:17 ` David Gow
2024-10-17 9:01 ` Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 03/10] um: Set parent death signal for userspace process Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 04/10] um: Set parent death signal for winch thread/process Benjamin Berg
2024-09-19 12:45 ` Benjamin Berg [this message]
2024-09-19 12:45 ` [PATCH v9 06/10] um: Calculate stub data address relative to stub code Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 07/10] um: Limit TASK_SIZE to the addressable range Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 08/10] um: Discover host_task_size from envp Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 09/10] um: clear all memory in new userspace processes Benjamin Berg
2024-09-19 12:45 ` [PATCH v9 10/10] um: Switch to 4 level page tables on 64 bit Benjamin Berg
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