From mboxrd@z Thu Jan 1 00:00:00 1970 From: kmagic@google.com Date: Mon, 1 Oct 2018 10:11:16 -0700 Subject: [LTP] [PATCH] Correct the kernel_bits value in x86 PER_LINUX32. Message-ID: <20181001171116.235573-1-kmagic@google.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it From: Kenneth Magic Android runs all 32bit programs in a PER_LIINUX32 personality even under a 64 bit kernel, causing the machine to show up as "i686". Check for and correct this case so tests use the correct kernel_bits value. Signed-off-by: Kenneth Magic --- lib/tst_kernel.c | 47 +++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 41 insertions(+), 6 deletions(-) diff --git a/lib/tst_kernel.c b/lib/tst_kernel.c index 4206e3c0d..d051f3b07 100644 --- a/lib/tst_kernel.c +++ b/lib/tst_kernel.c @@ -15,21 +15,28 @@ * along with this program. If not, see . */ +#include #include #include "test.h" #include "tst_kernel.h" -int tst_kernel_bits(void) +static int get_kernel_bits_from_uname(struct utsname *buf) { - struct utsname buf; - int kernel_bits; - - if (uname(&buf)) { + if (uname(buf)) { tst_brkm(TBROK | TERRNO, NULL, "uname()"); return -1; } - kernel_bits = strstr(buf.machine, "64") ? 64 : 32; + return strstr(buf->machine, "64") ? 64 : 32; +} + +int tst_kernel_bits(void) +{ + struct utsname buf; + int kernel_bits = get_kernel_bits_from_uname(&buf); + + if (kernel_bits == -1) + return -1; /* * ARM64 (aarch64) defines 32-bit compatibility modes as @@ -40,6 +47,34 @@ int tst_kernel_bits(void) || !strcmp(buf.machine, "s390x")) kernel_bits = 64; +#ifdef __ANDROID__ + /* Android's bionic libc sets the PER_LINUX32 personality for all 32-bit + * programs. This will cause buf.machine to report as i686 even though + * the kernel itself is 64-bit. + */ + if (!strcmp(buf.machine, "i686") && + (personality(0xffffffff) & PER_MASK) == PER_LINUX32) { + /* Set the personality back to the default. */ + if (personality(PER_LINUX) == -1) { + tst_brkm(TBROK | TERRNO, NULL, "personality()"); + return -1; + } + + /* Redo the uname check without the PER_LINUX32 personality to + * determine the actual kernel bits value. + */ + kernel_bits = get_kernel_bits_from_uname(&buf); + if (kernel_bits == -1) + return -1; + + /* Set the personality back to PER_LINUX32. */ + if (personality(PER_LINUX32) == -1) { + tst_brkm(TBROK | TERRNO, NULL, "personality()"); + return -1; + } + } +#endif /* __ANDROID__ */ + tst_resm(TINFO, "uname.machine=%s kernel is %ibit", buf.machine, kernel_bits); -- 2.19.0.605.g01d371f741-goog