Is the x86-64 kernel size limit real?

From: Olivier Galibert
Date: Thu Jun 22 2006 - 16:45:07 EST


I get bitched at by the build process because the kernel I get is
around 4.5Mb compressed. i386 does not have that limitation.
Interestingly, a diff between the two build.c gives:

--- ../../../i386/boot/tools/build.c 2006-06-22 20:19:33.000000000 +0200
+++ build.c 2006-06-22 20:19:33.000000000 +0200
@@ -70,8 +70,7 @@

int main(int argc, char ** argv)
{
- unsigned int i, sz, setup_sectors;
- int c;
+ unsigned int i, c, sz, setup_sectors;
u32 sys_size;
byte major_root, minor_root;
struct stat sb;
@@ -150,8 +149,10 @@
sz = sb.st_size;
fprintf (stderr, "System is %d kB\n", sz/1024);
sys_size = (sz + 15) / 16;
- if (!is_big_kernel && sys_size > DEF_SYSSIZE)
- die("System is too big. Try using bzImage or modules.");
+ /* 0x40000*16 = 4.0 MB, reasonable estimate for the current maximum */
+ if (sys_size > (is_big_kernel ? 0x40000 : DEF_SYSSIZE))
+ die("System is too big. Try using %smodules.",
+ is_big_kernel ? "" : "bzImage or ");
while (sz > 0) {
int l, n;


which shows two things:
1- a8f5034540195307362d071a8b387226b410469f should have a x86-64 version
2- the limit looks entirely artificial

So, is removing the limit prone to bite me?

OG.

PS: Please do not turn this thread into a pro/against modules ones, TYVM.
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