| Message ID | 1560975087-25632-5-git-send-email-andrew.cooper3@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | xen/link: Fixes and improvements to Xen's linking | expand |
Hi, On 6/19/19 9:11 PM, Andrew Cooper wrote: > * Drop .gnu.warning. Xen, not being a library, has no need for > __attribute__((__warning__("str"))) and isn't liable to ever gain such > annotations for link time warnings. What if this is introduced? How do we catch it? > * Adjust the indentation of the start of ARM's .rodata section. > * Discard .discard on ARM. Cheers,
On 19/06/2019 22:30, Julien Grall wrote: > Hi, > > On 6/19/19 9:11 PM, Andrew Cooper wrote: >> * Drop .gnu.warning. Xen, not being a library, has no need for >> __attribute__((__warning__("str"))) and isn't liable to ever gain >> such >> annotations for link time warnings. > > What if this is introduced? Then attempting to link Xen as a library against another object file won't emit the custom linker warning. Its main use is for phase-out of problematic API's, but for Xen (and other standalone binaries) we do that by replacing problematic functions entirely. > How do we catch it? Code review? ~Andrew
On Wed, Jun 19, 2019 at 09:11:27PM +0100, Andrew Cooper wrote: > * Drop .gnu.warning. Xen, not being a library, has no need for > __attribute__((__warning__("str"))) and isn't liable to ever gain such > annotations for link time warnings. > * Adjust the indentation of the start of ARM's .rodata section. > * Discard .discard on ARM. > > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> For x86: Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> Thanks, Roger.
Hi Andrew, On 6/19/19 10:38 PM, Andrew Cooper wrote: > On 19/06/2019 22:30, Julien Grall wrote: >> Hi, >> >> On 6/19/19 9:11 PM, Andrew Cooper wrote: >>> * Drop .gnu.warning. Xen, not being a library, has no need for >>> __attribute__((__warning__("str"))) and isn't liable to ever gain >>> such >>> annotations for link time warnings. >> >> What if this is introduced? > > Then attempting to link Xen as a library against another object file > won't emit the custom linker warning. Ok, so it is not like Xen will crash. > Its main use is for phase-out of problematic API's, but for Xen (and > other standalone binaries) we do that by replacing problematic functions > entirely. >> How do we catch it? > > Code review? I usually quite like when the tools help us to catch such issue :). Anyway, as this is not overly critical: Acked-by: Julien Grall <julien.grall@arm.com> Cheers,
>>> On 19.06.19 at 22:11, <andrew.cooper3@citrix.com> wrote: > * Drop .gnu.warning. Xen, not being a library, has no need for > __attribute__((__warning__("str"))) and isn't liable to ever gain such > annotations for link time warnings. > * Adjust the indentation of the start of ARM's .rodata section. > * Discard .discard on ARM. > > Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> x86: Acked-by: Jan Beulich <jbeulich@suse.com> Jan
diff --git a/xen/arch/arm/xen.lds.S b/xen/arch/arm/xen.lds.S index 3dc5117..c5ef5d5 100644 --- a/xen/arch/arm/xen.lds.S +++ b/xen/arch/arm/xen.lds.S @@ -35,14 +35,13 @@ SECTIONS *(.text.cold) *(.text.unlikely) *(.fixup) - *(.gnu.warning) _etext = .; /* End of text section */ } :text = 0x9090 . = ALIGN(PAGE_SIZE); .rodata : { - _srodata = .; /* Read-only data */ - /* Bug frames table */ + _srodata = .; /* Read-only data */ + /* Bug frames table */ __start_bug_frames = .; *(.bug_frames.0) __stop_bug_frames_0 = .; @@ -209,6 +208,8 @@ SECTIONS *(.exit.text) *(.exit.data) *(.exitcall.exit) + *(.discard) + *(.discard.*) *(.eh_frame) } diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S index ef11949..8bc2be3 100644 --- a/xen/arch/x86/xen.lds.S +++ b/xen/arch/x86/xen.lds.S @@ -82,7 +82,6 @@ SECTIONS *(.text.unlikely) *(.fixup) *(.text.kexec) - *(.gnu.warning) _etext = .; /* End of text section */ } :text = 0x9090
* Drop .gnu.warning. Xen, not being a library, has no need for __attribute__((__warning__("str"))) and isn't liable to ever gain such annotations for link time warnings. * Adjust the indentation of the start of ARM's .rodata section. * Discard .discard on ARM. Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> --- CC: Jan Beulich <JBeulich@suse.com> CC: Wei Liu <wl@xen.org> CC: Roger Pau Monné <roger.pau@citrix.com> CC: Stefano Stabellini <sstabellini@kernel.org> CC: Julien Grall <julien.grall@arm.com> --- xen/arch/arm/xen.lds.S | 7 ++++--- xen/arch/x86/xen.lds.S | 1 - 2 files changed, 4 insertions(+), 4 deletions(-)