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authorLinus Torvalds <torvalds@linux-foundation.org>2021-09-09 13:45:26 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-09-09 13:45:26 -0700
commitd6c338a741295c04ed84679153448b2fffd2c9cf (patch)
treec5711758bb97fb010157396815ab1dbc105d7247 /arch/x86
parent35776f10513c0d523c5dd2f1b415f642497779e2 (diff)
parentadf9ae0d159d3dc94f58d788fc4757c8749ac0df (diff)
downloadlinux-d6c338a741295c04ed84679153448b2fffd2c9cf.tar.bz2
Merge tag 'for-linus-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger: - Support for VMAP_STACK - Support for splice_write in hostfs - Fixes for virt-pci - Fixes for virtio_uml - Various fixes * tag 'for-linus-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: fix stub location calculation um: virt-pci: fix uapi documentation um: enable VMAP_STACK um: virt-pci: don't do DMA from stack hostfs: support splice_write um: virtio_uml: fix memory leak on init failures um: virtio_uml: include linux/virtio-uml.h lib/logic_iomem: fix sparse warnings um: make PCI emulation driver init/exit static
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/um/shared/sysdep/stub_32.h12
-rw-r--r--arch/x86/um/shared/sysdep/stub_64.h12
-rw-r--r--arch/x86/um/stub_segv.c3
3 files changed, 25 insertions, 2 deletions
diff --git a/arch/x86/um/shared/sysdep/stub_32.h b/arch/x86/um/shared/sysdep/stub_32.h
index b95db9daf0e8..4c6c2be0c899 100644
--- a/arch/x86/um/shared/sysdep/stub_32.h
+++ b/arch/x86/um/shared/sysdep/stub_32.h
@@ -101,4 +101,16 @@ static inline void remap_stack_and_trap(void)
"memory");
}
+static __always_inline void *get_stub_page(void)
+{
+ unsigned long ret;
+
+ asm volatile (
+ "movl %%esp,%0 ;"
+ "andl %1,%0"
+ : "=a" (ret)
+ : "g" (~(UM_KERN_PAGE_SIZE - 1)));
+
+ return (void *)ret;
+}
#endif
diff --git a/arch/x86/um/shared/sysdep/stub_64.h b/arch/x86/um/shared/sysdep/stub_64.h
index 6e2626b77a2e..e9c4b2b38803 100644
--- a/arch/x86/um/shared/sysdep/stub_64.h
+++ b/arch/x86/um/shared/sysdep/stub_64.h
@@ -108,4 +108,16 @@ static inline void remap_stack_and_trap(void)
__syscall_clobber, "r10", "r8", "r9");
}
+static __always_inline void *get_stub_page(void)
+{
+ unsigned long ret;
+
+ asm volatile (
+ "movq %%rsp,%0 ;"
+ "andq %1,%0"
+ : "=a" (ret)
+ : "g" (~(UM_KERN_PAGE_SIZE - 1)));
+
+ return (void *)ret;
+}
#endif
diff --git a/arch/x86/um/stub_segv.c b/arch/x86/um/stub_segv.c
index 21836eaf1725..f7eefba034f9 100644
--- a/arch/x86/um/stub_segv.c
+++ b/arch/x86/um/stub_segv.c
@@ -11,9 +11,8 @@
void __attribute__ ((__section__ (".__syscall_stub")))
stub_segv_handler(int sig, siginfo_t *info, void *p)
{
- int stack;
+ struct faultinfo *f = get_stub_page();
ucontext_t *uc = p;
- struct faultinfo *f = (void *)(((unsigned long)&stack) & ~(UM_KERN_PAGE_SIZE - 1));
GET_FAULTINFO_FROM_MC(*f, &uc->uc_mcontext);
trap_myself();