diff options
Diffstat (limited to 'examples/kernel-patches/2.4.x-revert-sysinfo.patch')
| -rw-r--r-- | examples/kernel-patches/2.4.x-revert-sysinfo.patch | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/examples/kernel-patches/2.4.x-revert-sysinfo.patch b/examples/kernel-patches/2.4.x-revert-sysinfo.patch new file mode 100644 index 0000000..c7cd5a7 --- /dev/null +++ b/examples/kernel-patches/2.4.x-revert-sysinfo.patch @@ -0,0 +1,77 @@ +I have a version of free I wrote for BusyBox that uses sysinfo (rather then +/proc) to get its information. Under 2.2.x it reports normal stuff, i.e. + [andersen@dillweed busybox]$ ./free + total used free shared buffers + Mem: 127800 124268 3532 16956 7544 + Swap: 128516 13584 114932 + Total: 256316 137852 118464 + +while under 2.2.0-test1-ac7 it reports wierd numbers (~ #/4096) + [andersen@dillweed busybox]$ ./free + total used free shared buffers + Mem: 30 11 19 0 1 + Swap: 31 0 31 + Total: 61 11 50 + +After investigating the problem, it turns out that somewhere during 2.3.x the +values for memory stored in struct sysinfo changed from being stored as bytes +to being units of PAGE_SIZE, but kernel/info.c was never updated to reflect +this change in definition. + +Breaking free isn't that big of a deal, but I also use sysinfo in init to check +that the box has enough ram from within the init process (and no, mounting +/proc from within init and reading /proc/meminfo is not a good solution. +BusyBox is often used in embedded systems where /proc is not compiled in). + +The following patch reinstates the traditional sysinfo(2) interface by +returning bytes (not units of PAGE_SIZE) for memory values. + +An additional patch suggestion (not included here) would be to eliminate the +supurfluous "mem_unit" variable from struct_sysinfo in include/linux/kernel.h +and arch/*/mm/init.c. + + -Erik + +-- +Erik B. Andersen Web: http://www.xmission.com/~andersen/ + email: andersee@debian.org +--This message was written using 73% post-consumer electrons-- + +--- linux/kernel/info.c.orig Mon Aug 23 12:15:53 1999 ++++ linux/kernel/info.c Sun Jun 4 01:13:11 2000 +@@ -2,6 +2,8 @@ + * linux/kernel/info.c + * + * Copyright (C) 1992 Darren Senn ++ * Fixed to once again return bytes instead of page counts, ++ * June 2000, by Erik Andersen <andersee@debian.org> + */ + + /* This implements the sysinfo() system call */ +@@ -10,7 +12,6 @@ + #include <linux/unistd.h> + #include <linux/swap.h> + #include <linux/smp_lock.h> +- + #include <asm/uaccess.h> + + asmlinkage long sys_sysinfo(struct sysinfo *info) +@@ -31,6 +32,17 @@ + + si_meminfo(&val); + si_swapinfo(&val); ++ ++ /* These are in units of PAGE_SIZE, but this interface ++ * has always returned bytes. Make it return bytes */ ++ val.totalram*=PAGE_SIZE; ++ val.freeram*=PAGE_SIZE; ++ val.sharedram*=PAGE_SIZE; ++ val.bufferram*=PAGE_SIZE; ++ val.totalswap*=PAGE_SIZE; ++ val.freeswap*=PAGE_SIZE; ++ val.totalhigh*=PAGE_SIZE; ++ val.freehigh*=PAGE_SIZE; + + if (copy_to_user(info, &val, sizeof(struct sysinfo))) + return -EFAULT; + |