[kvm-unit-tests PATCH 5/8] s390x: uv-host: Explain why we set up the home space and remove the space change
From: Janosch Frank <frankja@linux.ibm.com>
Date: 2021-08-13 07:37:41
Also in:
linux-s390
Subsystem:
the rest · Maintainer:
Linus Torvalds
UV home addresses don't require us to be in home space but we need to have it set up so hw/fw can use the home asce to translate home virtual addresses. Hence we add a comment why we're setting up the home asce and remove the address space since it's unneeded. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> --- s390x/uv-host.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/s390x/uv-host.c b/s390x/uv-host.c
index 426a67f6..28035707 100644
--- a/s390x/uv-host.c
+++ b/s390x/uv-host.c@@ -444,13 +444,18 @@ static void test_clear(void) static void setup_vmem(void) { - uint64_t asce, mask; + uint64_t asce; setup_mmu(get_max_ram_size(), NULL); + /* + * setup_mmu() will enable DAT and set the primary address + * space but we need to have a valid home space since UV calls + * take home space virtual addresses. + * + * Hence we just copy the primary asce into the home space. + */ asce = stctg(1); lctlg(13, asce); - mask = extract_psw_mask() | 0x0000C00000000000UL; - load_psw_mask(mask); } int main(void)
--
2.30.2