lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Fri, 27 Jul 2007 12:00:58 +1000
From:	Benjamin Herrenschmidt <>
To:	linux-mm <>
Cc:	Linux Kernel list <>
Subject: [PATCH/RFC] Add MM_DEAD flag to struct mm_struct

Some architectures like sparc can do useful optimizations when knowing
that an entire MM is being destroyed. At the moment, they rely on
fullmm in the mmu_gather structure. However, that doesn't always work
out very well with some of the changes we are doing. Among other things,
the TLB flushing on sparc64 is done using per-CPU tracking data, making
the batch not per-CPU will break that link.

So instead, we add a new flag to struct mm_struct that indicates that
the mm is going away, for those archs to use. It also allows to use it
in situations (such as PTE ops) where the batch isn't accessible (or
there is no batch)

Signed-off-by: Benjamin Herrenschmidt <>

Index: linux-work/include/linux/sched.h
--- linux-work.orig/include/linux/sched.h	2007-07-27 11:09:16.000000000 +1000
+++ linux-work/include/linux/sched.h	2007-07-27 11:09:22.000000000 +1000
@@ -353,6 +353,7 @@ extern int get_dumpable(struct mm_struct
 #define MMF_DUMPABLE      0  /* core dump is permitted */
 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
+#define MMF_DEAD          3  /* mm is being destroyed */
 /* coredump filter bits */
Index: linux-work/mm/mmap.c
--- linux-work.orig/mm/mmap.c	2007-07-27 11:09:52.000000000 +1000
+++ linux-work/mm/mmap.c	2007-07-27 11:10:05.000000000 +1000
@@ -1991,6 +1991,9 @@ void exit_mmap(struct mm_struct *mm)
 	unsigned long nr_accounted = 0;
 	unsigned long end;
+	/* Mark the MM as dead */
+	__set_bit(MMF_DEAD, &mm->flags);
 	/* mm's last user has gone, and its about to be pulled down */

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists