similar to: [PATCH] lguest: PAE support

Hi, For some days I have been looking for the bug that causes an easily reproducible oops in the guest when I apply my PAE support _draft_ patch (appended at the end of this mail) to lguest. This is the oops: Setting kernel variables...done. Will now mount local filesystems:. Will now activate swapfile swap:done. Cleaning /tmp... [ 84.749676] BUG: unable to handle kernel NULL pointer

Hi, For some days I have been looking for the bug that causes an easily reproducible oops in the guest when I apply my PAE support _draft_ patch (appended at the end of this mail) to lguest. This is the oops: Setting kernel variables...done. Will now mount local filesystems:. Will now activate swapfile swap:done. Cleaning /tmp... [ 84.749676] BUG: unable to handle kernel NULL pointer

If we're building a pte, we can use simple assigment; only use set_pte etc. when we're actually going to use that destination as a PTE. I don't know that we'll ever run under Xen, but it's neater. And use set_pte/set_pmd rather than assuming native_ versions, even though that's probably true for most people. (Includes compile fix by Kamalesh Babulal <kamalesh at

If we're building a pte, we can use simple assigment; only use set_pte etc. when we're actually going to use that destination as a PTE. I don't know that we'll ever run under Xen, but it's neater. And use set_pte/set_pmd rather than assuming native_ versions, even though that's probably true for most people. (Includes compile fix by Kamalesh Babulal <kamalesh at

From: Rusty Russell <rusty@rustcorp.com.au> This is the code for the "lg.ko" module, which allows lguest guests to be launched. [akpm@linux-foundation.org: update for futex-new-private-futexes] Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Andi Kleen <ak@suse.de> Cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton

From: Rusty Russell <rusty@rustcorp.com.au> This is the code for the "lg.ko" module, which allows lguest guests to be launched. [akpm@linux-foundation.org: update for futex-new-private-futexes] Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Andi Kleen <ak@suse.de> Cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton

plain text document attachment (lguest64.patch) This is the main core code for the lguest64. Have fun, and don't hurt the puppies! Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Glauber de Oliveira Costa <glommer@gmail.com> Cc: Chris Wright <chrisw@sous-sol.org> Index: work-pv/arch/x86_64/lguest/Makefile

plain text document attachment (lguest64.patch) This is the main core code for the lguest64. Have fun, and don't hurt the puppies! Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Glauber de Oliveira Costa <glommer@gmail.com> Cc: Chris Wright <chrisw@sous-sol.org> Index: work-pv/arch/x86_64/lguest/Makefile

Kernel pages on x86 are protected by not having the _PAGE_USER bit set. When guest userspace accesses a kernel page, we didn't check this, so we'd think we'd handled the fault and return to the guest, causing the guest userspace program to loop instead of segfaulting. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> --- drivers/lguest/core.c | 2 +-

Kernel pages on x86 are protected by not having the _PAGE_USER bit set. When guest userspace accesses a kernel page, we didn't check this, so we'd think we'd handled the fault and return to the guest, causing the guest userspace program to loop instead of segfaulting. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> --- drivers/lguest/core.c | 2 +-

Impact: potential bugfix In theory, the kernel could reuse the same page as pgdir for a new process while the hypervisor keeps it cached. This would have undesirable results. Signed-off-by: Rusty Russell <rusty at rustcorp.com.au> --- arch/x86/include/asm/lguest_hcall.h | 1 + arch/x86/lguest/boot.c | 8 ++++++++ drivers/lguest/hypercalls.c | 3 +++

Impact: potential bugfix In theory, the kernel could reuse the same page as pgdir for a new process while the hypervisor keeps it cached. This would have undesirable results. Signed-off-by: Rusty Russell <rusty at rustcorp.com.au> --- arch/x86/include/asm/lguest_hcall.h | 1 + arch/x86/lguest/boot.c | 8 ++++++++ drivers/lguest/hypercalls.c | 3 +++

[Bug that was found by my previous patch] This patch allows things like modules, which don't have a direct __pa(EIP) mapping to do emulated instructions. Sure, the emulated instruction probably should be a paravirt_op, but this patch lets you at least boot a kernel that has modules needing emulated instructions. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Index:

[Bug that was found by my previous patch] This patch allows things like modules, which don't have a direct __pa(EIP) mapping to do emulated instructions. Sure, the emulated instruction probably should be a paravirt_op, but this patch lets you at least boot a kernel that has modules needing emulated instructions. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Index:

This series takes one more step towards cpu-ification of lguest. As for rusty's last suggestion, I get rid of the whole bunch of "struct lguest *lg = cpu->lg" statements around by using lg_cpu as our base structure wherever it matters. (this saves us 11 lines)

This series takes one more step towards cpu-ification of lguest. As for rusty's last suggestion, I get rid of the whole bunch of "struct lguest *lg = cpu->lg" statements around by using lg_cpu as our base structure wherever it matters. (this saves us 11 lines)

The following changes since commit 3c92ec8ae91ecf59d88c798301833d7cf83f2179: Linus Torvalds (1): Merge branch 'next' of git://git.kernel.org/.../paulus/powerpc are available in the git repository at: ssh://master.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus.git master

The following changes since commit 3c92ec8ae91ecf59d88c798301833d7cf83f2179: Linus Torvalds (1): Merge branch 'next' of git://git.kernel.org/.../paulus/powerpc are available in the git repository at: ssh://master.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus.git master

Hi, In many places xen uses "unsigned long" instead of the l*_pgentry_t types to pass around page table entries. Here is a patch which fixes this in a number of places (mostly in shadow mode code). Thats what I''ve trapped in so far, maybe more of these patches follow. Fixing this is needed for adding PAE support to xen. In PAE paging mode the page table entries are 64 bit

Hi all, I've been working on lguest64 and in order to do this, I had to move a lot of the i386 specific out of the way. Well, the lguest64 port is still not ready to display, but before Rusty makes too many changes I would like this in upstream so I don't have to keep repeating my changes :-) So this patch series moves lguest32 out of the way for other archs. -- Steve