From 770275ed0c0ab05677472efcf184b1a02ab14d07 Mon Sep 17 00:00:00 2001 From: Joe Richey Date: Tue, 3 Mar 2020 02:52:47 -0800 Subject: optionrom/pvh: scan entire RSDP Area Right now the PVH option rom scans for the RSDP from 0xE0000 to 0xE1FFF. This is probobly a typo, it should scan from 0xE0000 to 0xFFFFF. This is actually an issue on some QEMU versions/machines. For example, when I run QEMU the RSDP is placed at 0xf5ad0 which will not be picked up by the current implementation. This bug still allows a Linux guest to boot (in most configurations) as the kernel will just scan for the RSDP if one isn't provided. Signed-off-by: Joe Richey Reviewed-by: Stefano Garzarella Fixes: 2785dc7b17 ("optionrom: add new PVH option rom") Signed-off-by: Paolo Bonzini --- pc-bios/optionrom/pvh_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'pc-bios') diff --git a/pc-bios/optionrom/pvh_main.c b/pc-bios/optionrom/pvh_main.c index a015e1b..28e79d7 100644 --- a/pc-bios/optionrom/pvh_main.c +++ b/pc-bios/optionrom/pvh_main.c @@ -29,7 +29,7 @@ asm (".code32"); /* this code will be executed in protected mode */ #define RSDP_SIGNATURE 0x2052545020445352LL /* "RSD PTR " */ #define RSDP_AREA_ADDR 0x000E0000 -#define RSDP_AREA_SIZE 2048 +#define RSDP_AREA_SIZE 0x00020000 #define EBDA_BASE_ADDR 0x0000040E #define EBDA_SIZE 1024 -- cgit v1.1 From f7795e4096d8bd1c767c5ddb450fa859ff20490e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Wed, 4 Mar 2020 16:38:15 +0100 Subject: misc: Replace zero-length arrays with flexible array member (automatic) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Description copied from Linux kernel commit from Gustavo A. R. Silva (see [3]): --v-- description start --v-- The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member [1], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being unadvertenly introduced [2] to the Linux codebase from now on. --^-- description end --^-- Do the similar housekeeping in the QEMU codebase (which uses C99 since commit 7be41675f7cb). All these instances of code were found with the help of the following Coccinelle script: @@ identifier s, m, a; type t, T; @@ struct s { ... t m; - T a[0]; + T a[]; }; @@ identifier s, m, a; type t, T; @@ struct s { ... t m; - T a[0]; + T a[]; } QEMU_PACKED; [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76497732932f [3] https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?id=17642a2fbd2c1 Inspired-by: Gustavo A. R. Silva Reviewed-by: David Hildenbrand Signed-off-by: Philippe Mathieu-Daudé Signed-off-by: Paolo Bonzini --- pc-bios/s390-ccw/bootmap.h | 2 +- pc-bios/s390-ccw/sclp.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'pc-bios') diff --git a/pc-bios/s390-ccw/bootmap.h b/pc-bios/s390-ccw/bootmap.h index 94f53a5..12a0166 100644 --- a/pc-bios/s390-ccw/bootmap.h +++ b/pc-bios/s390-ccw/bootmap.h @@ -136,7 +136,7 @@ typedef struct BootMapScriptHeader { typedef struct BootMapScript { BootMapScriptHeader header; - BootMapScriptEntry entry[0]; + BootMapScriptEntry entry[]; } __attribute__ ((packed)) BootMapScript; /* diff --git a/pc-bios/s390-ccw/sclp.h b/pc-bios/s390-ccw/sclp.h index 8450161..64b53ca 100644 --- a/pc-bios/s390-ccw/sclp.h +++ b/pc-bios/s390-ccw/sclp.h @@ -95,7 +95,7 @@ typedef struct EventBufferHeader { typedef struct WriteEventData { SCCBHeader h; EventBufferHeader ebh; - char data[0]; + char data[]; } __attribute__((packed)) WriteEventData; typedef struct ReadEventData { -- cgit v1.1