similar to: [PATCH v4 00/10] x86: Support compiling out userspace IO (iopl and ioperm)

This patch series makes it possible to compile out the iopl and ioperm system calls, which allow privileged processes to request permission to directly poke I/O ports from userspace. Nothing on a modern Linux system uses these calls anymore, and anything new should be using /dev/port instead, or better yet writing a driver. Copying the bloat-o-meter stats from the final patch: 32-bit

This patch series makes it possible to compile out the iopl and ioperm system calls, which allow privileged processes to request permission to directly poke I/O ports from userspace. Nothing on a modern Linux system uses these calls anymore, and anything new should be using /dev/port instead, or better yet writing a driver. Copying the bloat-o-meter stats from the final patch: 32-bit

The 32-bit and 64-bit versions of copy_thread have functionally identical handling for copying the I/O bitmap, modulo differences in error handling. Clean up the error paths in both by moving the copy of the I/O bitmap to the end, to eliminate the need to free it if subsequent copy steps fail; move the resulting identical code to a static inline in a common header. Signed-off-by: Josh Triplett

The 32-bit and 64-bit versions of copy_thread have functionally identical handling for copying the I/O bitmap, modulo differences in error handling. Clean up the error paths in both by moving the copy of the I/O bitmap to the end, to eliminate the need to free it if subsequent copy steps fail; move the resulting identical code to a static inline in a common header. Signed-off-by: Josh Triplett

The 32-bit and 64-bit versions of copy_thread have functionally identical handling for copying the I/O bitmap, modulo differences in error handling. Clean up the error paths in both by moving the copy of the I/O bitmap to the end, to eliminate the need to free it if subsequent copy steps fail; move the resulting identical code to a static inline in a common header. Signed-off-by: Josh Triplett

The 32-bit and 64-bit versions of copy_thread have functionally identical handling for copying the I/O bitmap, modulo differences in error handling. Clean up the error paths in both by moving the copy of the I/O bitmap to the end, to eliminate the need to free it if subsequent copy steps fail; move the resulting identical code to a static inline in a common header. Signed-off-by: Josh Triplett

Hi Josh, On Tue, Oct 22, 2013, at 3:35, Josh Triplett wrote: > On the vast majority of modern systems, no processes will use the > userspsace I/O syscalls, iopl and ioperm. Add a new config option, > CONFIG_X86_IOPORT, to support configuring them out of the kernel > entirely. Since these syscalls only exist to support rare legacy > userspace programs, X86_IOPORT does not depend

Hi Josh, On Tue, Oct 22, 2013, at 3:35, Josh Triplett wrote: > On the vast majority of modern systems, no processes will use the > userspsace I/O syscalls, iopl and ioperm. Add a new config option, > CONFIG_X86_IOPORT, to support configuring them out of the kernel > entirely. Since these syscalls only exist to support rare legacy > userspace programs, X86_IOPORT does not depend

On the vast majority of modern systems, no processes will use the userspsace I/O syscalls, iopl and ioperm. Add a new config option, CONFIG_X86_IOPORT, to support configuring them out of the kernel entirely. Most current systems do not run programs using these syscalls, so X86_IOPORT does not depend on EXPERT, though it does still default to y. In addition to saving a significant amount of

On the vast majority of modern systems, no processes will use the userspsace I/O syscalls, iopl and ioperm. Add a new config option, CONFIG_X86_IOPORT, to support configuring them out of the kernel entirely. Most current systems do not run programs using these syscalls, so X86_IOPORT does not depend on EXPERT, though it does still default to y. In addition to saving a significant amount of

On Wed, Oct 29, 2014 at 9:10 AM, Josh Triplett <josh at joshtriplett.org> wrote: > On the vast majority of modern systems, no processes will use the > userspsace I/O syscalls, iopl and ioperm. Add a new config option, > CONFIG_X86_IOPORT, to support configuring them out of the kernel > entirely. Most current systems do not run programs using these > syscalls, so X86_IOPORT

On the vast majority of modern systems, no processes will use the userspsace I/O syscalls, iopl and ioperm. Add a new config option, CONFIG_X86_IOPORT, to support configuring them out of the kernel entirely. Since these syscalls only exist to support rare legacy userspace programs, X86_IOPORT does not depend on EXPERT, though it does still default to y. In addition to saving a significant

On the vast majority of modern systems, no processes will use the userspsace I/O syscalls, iopl and ioperm. Add a new config option, CONFIG_X86_IOPORT, to support configuring them out of the kernel entirely. Most current systems do not run programs using these syscalls, so X86_IOPORT does not depend on EXPERT, though it does still default to y. In addition to saving a significant amount of

I/O from userspace is used to implement usermode virtio driver(s). This has been done independently by Intel, Brocade/Vyatta, and 6Wind. Sorry, it has to stay. On Mon, Oct 21, 2013 at 7:35 PM, Josh Triplett <josh at joshtriplett.org> wrote: > On the vast majority of modern systems, no processes will use the > userspsace I/O syscalls, iopl and ioperm. Add a new config option, >

I/O from userspace is used to implement usermode virtio driver(s). This has been done independently by Intel, Brocade/Vyatta, and 6Wind. Sorry, it has to stay. On Mon, Oct 21, 2013 at 7:35 PM, Josh Triplett <josh at joshtriplett.org> wrote: > On the vast majority of modern systems, no processes will use the > userspsace I/O syscalls, iopl and ioperm. Add a new config option, >

Hi Josh, Since you added me to the CC, I had a look... Comments inline On Tue, Oct 22, 2013, at 3:34, Josh Triplett wrote: > The 32-bit and 64-bit versions of copy_thread have functionally > identical handling for copying the I/O bitmap, modulo differences in > error handling. Clean up the error paths in both by moving the copy of > the I/O bitmap to the end, to eliminate the need

Hi Josh, Since you added me to the CC, I had a look... Comments inline On Tue, Oct 22, 2013, at 3:34, Josh Triplett wrote: > The 32-bit and 64-bit versions of copy_thread have functionally > identical handling for copying the I/O bitmap, modulo differences in > error handling. Clean up the error paths in both by moving the copy of > the I/O bitmap to the end, to eliminate the need

On the vast majority of modern systems, no processes will use the userspsace IO syscalls, iopl and ioperm. Add a new config option, CONFIG_X86_IOPORT, to support configuring them out of the kernel entirely. Most current systems do not run programs using these syscalls, so X86_IOPORT does not depend on EXPERT, though it does still default to y. In addition to saving a significant amount of

On the vast majority of modern systems, no processes will use the userspsace IO syscalls, iopl and ioperm. Add a new config option, CONFIG_X86_IOPORT, to support configuring them out of the kernel entirely. Most current systems do not run programs using these syscalls, so X86_IOPORT does not depend on EXPERT, though it does still default to y. In addition to saving a significant amount of

The 32-bit and 64-bit versions of copy_thread have functionally identical handling for copying the I/O bitmap, modulo differences in error handling. Clean up the error paths in both by moving the copy of the I/O bitmap to the end, to eliminate the need to free it if subsequent copy steps fail; move the resulting identical code to a static inline in a common header. Signed-off-by: Josh Triplett