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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-21 13:53:00 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-21 13:53:00 -0800 |
| commit | 04471d3f18cb9a2155797c810670196c05dd9f78 (patch) | |
| tree | 6649c992996e5075705244475a09d3bf760c0a45 /arch/x86/um/stub_32.S | |
| parent | df24212a493afda0d4de42176bea10d45825e9a0 (diff) | |
| parent | ddad5187fc2a12cb84c9d1ac8ecb816708a2986b (diff) | |
Merge tag 'for-linux-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
- Many cleanups and fixes for our virtio code
- Add support for a pseudo RTC
- Fix for a possible jailbreak
- Minor fixes (spelling, header files)
* tag 'for-linux-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: irq.h: include <asm-generic/irq.h>
um: io.h: include <linux/types.h>
um: add a pseudo RTC
um: remove process stub VMA
um: rework userspace stubs to not hard-code stub location
um: separate child and parent errors in clone stub
um: defer killing userspace on page table update failures
um: mm: check more comprehensively for stub changes
um: print register names in wait_for_stub
um: hostfs: use a kmem cache for inodes
mm: Remove arch_remap() and mm-arch-hooks.h
um: fix spelling mistake in Kconfig "privleges" -> "privileges"
um: virtio: allow devices to be configured for wakeup
um: time-travel: rework interrupt handling in ext mode
um: virtio: disable VQs during suspend
um: virtio: fix handling of messages without payload
um: virtio: clean up a comment
Diffstat (limited to 'arch/x86/um/stub_32.S')
| -rw-r--r-- | arch/x86/um/stub_32.S | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/arch/x86/um/stub_32.S b/arch/x86/um/stub_32.S index a193e88536a9..8291899e6aaf 100644 --- a/arch/x86/um/stub_32.S +++ b/arch/x86/um/stub_32.S @@ -5,21 +5,22 @@ .globl batch_syscall_stub batch_syscall_stub: - /* load pointer to first operation */ - mov $(STUB_DATA+8), %esp - + /* %esp comes in as "top of page" */ + mov %esp, %ecx + /* %esp has pointer to first operation */ + add $8, %esp again: /* load length of additional data */ mov 0x0(%esp), %eax /* if(length == 0) : end of list */ /* write possible 0 to header */ - mov %eax, STUB_DATA+4 + mov %eax, 0x4(%ecx) cmpl $0, %eax jz done /* save current pointer */ - mov %esp, STUB_DATA+4 + mov %esp, 0x4(%ecx) /* skip additional data */ add %eax, %esp @@ -38,6 +39,10 @@ again: /* execute syscall */ int $0x80 + /* restore top of page pointer in %ecx */ + mov %esp, %ecx + andl $(~UM_KERN_PAGE_SIZE) + 1, %ecx + /* check return value */ pop %ebx cmp %ebx, %eax @@ -45,7 +50,7 @@ again: done: /* save return value */ - mov %eax, STUB_DATA + mov %eax, (%ecx) /* stop */ int3 |