Re: error: impossible constraint in 'asm' when compiling kernel code with -O0 option

2021-10-05 Thread Jeffrey Walton
On Tue, Oct 5, 2021 at 10:59 PM wrote: > > In linux-5.4.21 code, > > To prevent some variables from being ‘optimized out’ during kernel code > analysis using gdb, I added in drivers/iommu/Makefile, > ... > ./include/linux/compiler-gcc.h:120:38: error: impossible constraint in 'asm' > > 120 |

error: impossible constraint in 'asm' when compiling kernel code with -O0 option

2021-10-05 Thread ckim
In linux-5.4.21 code, To prevent some variables from being 'optimized out' during kernel code analysis using gdb, I added in drivers/iommu/Makefile, (replacing -O2 flags to -O0 flags for some files, I found http://www.joelfernandes.org/linux/2018/06/10/kernel-gdb.html )

Re: advice on checkpatch error

2021-10-05 Thread jim . cromie
On Tue, Oct 5, 2021 at 1:14 PM wrote: > > so I have this macro, with some helpers, > the helper gets a checkpatch error. > > DEFINE_DYNAMIC_DEBUG_CATEGORIES(debug_gvt, __gvt_debug, > "i915/gvt bitmap desc", > /* map each bit to a category */ > _DD_cat_(0,

advice on checkpatch error

2021-10-05 Thread jim . cromie
so I have this macro, with some helpers, the helper gets a checkpatch error. DEFINE_DYNAMIC_DEBUG_CATEGORIES(debug_gvt, __gvt_debug, "i915/gvt bitmap desc", /* map each bit to a category */ _DD_cat_(0, "gvt:cmd:"), _DD_cat_(1, "gvt:core:"),