From: Abhinav Singh <singhabhinav9051571833@xxxxxxxxx> Sent: Monday, October 30, 2023 3:50 PM > > This patch fixes two sparse warnings > > 1. sparse complaining about the removal of __iomem address > space when casting the return value of this ioremap_cache(...) > from `void __ioremap*` to `void*`. > Fixed this by replacing the ioremap_cache(...) > by memremap(...) and using MEMREMAP_DEC and MEMREMAP_WB flag for > making > sure the memory is always decrypted and it will support full write back > cache. > > 2. sparse complaining `expected void volatile [noderef] __iomem *addr` > when calling iounmap with a non __iomem pointer. > Fixed this by replacing iounmap(...) with memumap(...). > > Signed-off-by: Abhinav Singh <singhabhinav9051571833@xxxxxxxxx> Since Nischala has posted her more comprehensive patch, this patch can be dropped. But see one comment below for future reference. > --- > > v1: > https://lore.kernel.org/all/19cec6f0-e176-4bcc-95a0-9d6eb0261ed1@xxxxxxxxx/T/ > > v1 to v2: > 1. Fixed the comment which was earlier describing ioremap_cache(...). > 2. Replaced iounmap(...) with memremap(...) inside function hv_cpu_die(...). > > arch/x86/hyperv/hv_init.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > index 21556ad87f4b..2a14928b8a36 100644 > --- a/arch/x86/hyperv/hv_init.c > +++ b/arch/x86/hyperv/hv_init.c > @@ -68,9 +68,11 @@ static int hyperv_init_ghcb(void) > */ > rdmsrl(MSR_AMD64_SEV_ES_GHCB, ghcb_gpa); > > - /* Mask out vTOM bit. ioremap_cache() maps decrypted */ > + /* Mask out vTOM bit. > + MEMREMAP_WB full write back cache > + MEMREMAP_DEC maps decrypted memory */ This isn't the right style for multi-line patches. Correct would be: /* * Mask out vTOM bit. * MEMREMAP_WB full write back cache * MEMREMAP_DEC maps decrypted memory */ Section 8 of coding-style.rst under Documentation/process covers these details. Note that the style is slightly different for code under net and drivers/net. Michael > ghcb_gpa &= ~ms_hyperv.shared_gpa_boundary; > - ghcb_va = (void *)ioremap_cache(ghcb_gpa, HV_HYP_PAGE_SIZE); > + ghcb_va = memremap(ghcb_gpa, HV_HYP_PAGE_SIZE, MEMREMAP_WB | MEMREMAP_DEC); > if (!ghcb_va) > return -ENOMEM; > > @@ -238,7 +240,7 @@ static int hv_cpu_die(unsigned int cpu) > if (hv_ghcb_pg) { > ghcb_va = (void **)this_cpu_ptr(hv_ghcb_pg); > if (*ghcb_va) > - iounmap(*ghcb_va); > + memunmap(*ghcb_va); > *ghcb_va = NULL; > } > > -- > 2.39.2
