This was added erroneously by me.

Hardware task switching does demand a TSS of at least 0x67 bytes, but that's
not relevant in 64bit, and not relevant for Xen since commit
5d1181a5ea5e ("xen: Remove x86_32 build target.") in 2012.

We already load a 0-length TSS in early_traps_init() demonstrating that it's
possible.

Signed-off-by: Andrew Cooper <andrew.coop...@citrix.com>
---
CC: Jan Beulich <jbeul...@suse.com>
CC: Roger Pau Monné <roger....@citrix.com>
---
 xen/arch/x86/cpu/common.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/xen/arch/x86/cpu/common.c b/xen/arch/x86/cpu/common.c
index f6ec5c9df522..cdc41248d4e9 100644
--- a/xen/arch/x86/cpu/common.c
+++ b/xen/arch/x86/cpu/common.c
@@ -936,8 +936,6 @@ void load_system_tables(void)
                wrmsrl(MSR_ISST, (unsigned long)ist_ssp);
        }
 
-       BUILD_BUG_ON(sizeof(*tss) <= 0x67); /* Mandated by the architecture. */
-
        _set_tssldt_desc(gdt + TSS_ENTRY, (unsigned long)tss,
                         sizeof(*tss) - 1, SYS_DESC_tss_avail);
        if ( IS_ENABLED(CONFIG_PV32) )
-- 
2.39.5


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